Vacuum coagulation probes

ABSTRACT

A surgical device integrating a suction mechanism with a coagulation mechanism is provided for improving lesion creation capabilities. The device comprises an elongate member having an insulative covering attached about means for coagulating soft tissue. Openings through the covering expose regions of the coagulation-causing elements and are coupled to lumens in the elongate member which are routed to a vacuum source. A fluid source to passively transport fluid along the contacted soft tissue surface may be provided in order to push the maximum temperature deeper into tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/558,420 filed Nov. 9, 2006, which is a continuation-in-part of U.S.patent application Ser. No. 11/432,962 filed May 12, 2006 (now U.S. Pat.No. 7,780,661 issued Aug. 24, 2010), which is a continuation of U.S.patent application Ser. No. 10/425,251 filed Apr. 29, 2003 (now U.S.Pat. No. 7,063,698 issued Jun. 20, 2006), which is acontinuation-in-part of U.S. patent application Ser. No. 10/172,296filed Jun. 14, 2002 (now U.S. Pat. No. 6,893,442 issued May 17, 2005)each of which is incorporated herein by reference in its entirety.

BACKGROUND

Atrial fibrillation surgery involving radiofrequency, D.C., microwave,or other thermal ablation of atrial tissue has a limitation in thattissue contact throughout the length of the electrode(s) is/are notconsistent causing variability in the transmission of energy throughoutthe target length of ablated/coagulated tissue. This produces gaps ofviable tissue that promote propagation of wavelets that sustain atrialfibrillation, or produce atrial flutter, atrial tachycardia, or otherarrhythmia substrate.

Another influence in the inability of existing thermal ablation probesto create complete curvilinear, transmural lesions is the presence ofconvective cooling on the opposite surface of the atrium producing aheat sink that decreases the maximum temperature at this surface therebypreventing the lesions from consistently extending transmurally throughthe entire wall of the atrium. This is especially relevant duringbeating-heart procedures in which the coagulation/ablation probe isplaced against the epicardial surface, and blood flowing along theendocardium removes heat thus producing a larger gradient betweentemperature immediately under the probe electrodes along the epicardiumand that at the endocardium.

Another deficiency of current approaches is the inability to direct thecoagulation of precise regions of soft tissue while avoiding underlyingor nearby tissue structures. For example, atrial fibrillation ablationmay involve extending a lesion to the annulus near which the circumflex,right coronary artery, and coronary sinus reside; another exampleinvolves ablating ventricular tachycardia substrates that reside nearcoronary arteries or coronary veins. Conventional approaches are unableto selectively ablate desired soft tissue structures and isolatepreserved tissue structures from targeted regions.

Aspects of the invention address at least some of these deficiencies foratrial fibrillation and ventricular tachycardia ablation. In addition,the variations of the invention address similar deficiencies, which areapparent during other applications involving coagulation of a selectedtissue region in a precise manner such as cancer ablation, soft tissueshrinking, and articular cartilage removal.

SUMMARY OF THE INVENTION

Aspects of the invention are directed to devices and methods for lessinvasive treatment of atrial fibrillation. The subject coagulationprobes for ablation and/or coagulation integrate suction to thecoagulation mechanism so as to ensure consistent and intimate tissuecontact directly between the coagulation mechanism and soft tissue. Thesubject coagulation probes may also have features allowing foradvancement or positioning of the probes using a track-member asdescribed below.

Increased tissue contact relative to that which can be achieved withknown devices is capable of reversing convective cooling effects effectnoted above by evoking a compression of the tissue that shortens thewall thickness (e.g., of the atria), ensuring consistent contactthroughout the length of the electrode(s), and increasing the efficiencyof thermal conduction from the epicardium to the endocardium. As such amore consistent and reliable lesion is created.

As such, the integrated vacuum-assisted coagulation probes of thesubject invention are capable of reliably creating transmural,curvilinear lesions capable of preventing the propagation of waveletsthat initiate and sustain atrial fibrillation, atrial flutter,ventricular tachycardia, or other arrhythmia substrate.

The vacuum-assisted coagulation probes also facilitate minimallyinvasive surgery involving endoscopic or laparoscopic access andvisualization to the target coagulation sites. Additionally, thevacuum-assisted coagulation probes of the invention are suitable forcoagulating or ablating soft tissues (e.g., atrial tissue to treatatrial fibrillation, atrial flutter, or other supraventriculartachycardia; or ventricular tissue to treat ventricular tachycardia)through a median sternotomy, lateral thoracotomy, intercostalsport-access, mini-sternotomies, other less invasive approaches involvingsubxiphoid access, subclavian access, inguinal approaches, orsub-thoracic approaches adjacent or through the diaphragm.Alternatively, the vacuum-integrated coagulation probes can be modifiedfor catheter-based applications by elongating the shaft, altering thedimensions of the device, and incorporating other features tailored forintravascular access and manipulation.

The present invention includes systems comprising any combination of thefeatures described herein. The probes may use any of an electricallyresistive heated, RF, vibrational/ultrasonic transmission element orelements as described herein as a tissue heating element. The variousstructures described for applying energy to heat tissue may be regardedas the various means for tissue coagulation disclosed herein.Methodology described in association with the devices disclosed alsoforms part of the invention.

Such methodology may include that associated with coagulating other softtissues for a variety of applications including cancer therapy (e.g.,liver, prostate, colon, esophageal, gastrointestinal, gynecological,etc.); Gastro-esophageal Reflux Disease treatment; shrinking ofcollagen-based tissue structures such as skin, tendons, muscles,ligaments, vascular tissue during arthroscopic, laparoscopic, or otherminimally invasive procedures; and/or coagulation of an upper layer oftissue without damaging underlying tissue structures, for example duringarticular cartilage removal.

Similar coagulation probes are disclosed in: U.S. patent applicationSer. No. 11/408,302 entitled “Vacuum Coagulation Probes”; U.S. patentapplication Ser. No. 11/208,465 entitled “Vacuum Coagulation &Dissection Probes”; U.S. patent application Ser. No. 10/425,251 entitled“Vacuum Coagulation Probes”; U.S. Provisional application No. 60/726,342entitled Diaphragm Entry for Posterior Access Surgical Procedures; andU.S. Pat. No. 6,893,442 the entirety of each of which is herebyincorporated by reference.

BRIEF DESCRIPTION OF DRAWINGS

Each of the figures diagrammatically illustrates aspects of theinvention. Of these:

FIG. 1A shows an example of a coagulation probe;

FIG. 1B shows a side view of the coagulation probe of FIG. 1A;

FIG. 1C shows a cross sectional view of the coagulation probe of FIG.1A;

FIG. 1D shows a cross sectional view taken along lines 1D-1D of FIG. 1C;

FIG. 1E shows a bottom view of a coagulation probe;

FIGS. 1F to 1G show a spine member attached to a tether and placement ofthe spine and tether in the elongate housing respectively;

FIG. 1H shows a variation of an element for use with the coagulationprobe;

FIGS. 1I to 1K show various shapes of coagulation probes;

FIGS. 2A to 2B show elongate housing members having a main lumenextending across a top of the housing;

FIGS. 2C to 2D show a perfusion or fluid supply lumen within the mainlumen where both lumens extend across a top of the housing;

FIG. 2E shows a variation of a coagulation probe having features toaccommodate a track member used to position the probe;

FIG. 2F shows a detail view of a probe housing with a track extendingout of a track lumen of the housing;

FIGS. 2G to 2I show a variation of an optional plug used to couple aperfusion lumen with a main cavity;

FIG. 2J shows a variation of a coagulation probe where a track extendsthrough a main lumen, a main cavity and through a distal end of ahousing;

FIGS. 2K to 2L show a method of using a probe and track to treat tissue;

FIGS. 3A to 3C illustrate a variation of a sensing probe having featuresdescribed herein;

FIG. 4A shows a variation of a double tether affixed to an elongatehousing;

FIG. 4B shows an example of a guiding stylet for use with variousprobes;

FIGS. 5A and 5B show an isometric view, and a side view of an assembledintegrated vacuum-integrated coagulation probe variation;

FIGS. 6A to 6F show an exploded view, a bottom view, a side sectionalview, two isometric views, and a cross-sectional view of the distal endof the vacuum-integrated coagulation probe variation in FIGS. 5A and 5B;

FIGS. 7A to 7I show an isometric view, a bottom view, a side sectionalview, a side view and five cross-sectional views of the distal end ofanother vacuum-integrated coagulation probe variation;

FIGS. 8A to 8C shows an isometric view, a side view, and an end view ofa modular, lockable, external rail mechanism that is able to lock andmaneuver the vacuum-integrated coagulation probe along a directed path;

FIGS. 9A to 9D show an isometric view, a top view, a side view, and anend view of a vacuum-integrated coagulation probe variation supported bythe rail mechanism in FIGS. 8A to 8C;

FIG. 10 shows a perspective view of an alternative external guidevariation;

FIGS. 11A and 11B show an isometric view and a side view of a locking,elliptical trocar system;

FIG. 11C shows a side view of the puncturing dilator for the trocar inFIGS. 11A and 11B;

FIG. 11D shows a top view of the trocar system in FIGS. 11A and 11B;

FIG. 11E shows a top view of the trocar sheath in FIGS. 11A and 11B;

FIGS. 12A to 12C show an isometric view, a side view, and a top view ofthe trocar sheath in FIGS. 11A to 11E in a deployed and lockedorientation;

FIGS. 13A to 13C show an isometric view, a side view, and a bottom viewof a vacuum-integrated theranostic probe variation;

FIG. 14 shows an isometric view of an alternative vacuum-integratedtheranostic probe;

FIGS. 15A and 15B show an isometric view and an end view of theintegrated electrode of the theranostic probe in FIGS. 13A to 13C;

FIGS. 16A and 16B show an isometric view and an end view of theintegrated electrode of the theranostic probe in FIG. 14;

FIGS. 17A to 17E show an isometric view, a front view, a side view, abottom view, and a sectional view of another theranostic probevariation;

FIGS. 18A to 18C show an isometric view, a side view, and aside-sectional view of the distal end of a vacuum-integrated dissectingtool/coagulation probe variation;

FIGS. 19A to 19G show an isometric view, a side view, a bottom view, aside-sectional view, and three cross-sectional views of the distal endof another vacuum-integrated dissecting tool/coagulation probevariation;

FIG. 19H shows an isometric view of the distal end of the rotatingdissecting/coagulating component of the variation in FIGS. 19A to 19G;

FIGS. 20A to 20D show an isometric view, a side view, a top view, and anend view of a dissecting/tunneling instrument;

FIGS. 21A to 21C show sectional views of the dissecting/tunnelinginstrument in FIGS. 20A to 20D without the handle actuated, with thedissecting loops expanded, and with the integrated steering mechanismactuated respectively;

FIG. 22 shows a sectional view of an alternative dissecting/tunnelinginstrument variation;

FIGS. 23A to 23C show an isometric view, a side view, and a top view ofa mechanically vibrating ultrasonic ablation catheter variation;

FIGS. 24A to 24C show an isometric view, a side view, and a top view ofanother mechanically vibrating ultrasonic ablation catheter variation;

FIGS. 25A and 25B show an isometric view, an end view, and a sectionalview of the mechanically vibrating ultrasonic ablation catheter in FIGS.23A to 23C inside a pulmonary vein;

FIGS. 26A and 26B show an isometric view, an end view, and a sectionalview of the mechanically vibrating ultrasonic ablation catheter in FIGS.24A to 24C inside a pulmonary vein;

FIGS. 27A to 27C show an exploded view, a bottom view, a close-up view,respectively, of an integrated vacuum coagulation probe variation of theinvention;

FIGS. 28A to 28C show a side view, a perspective view, and a bottom viewof the distal section of an integrated vacuum coagulation probevariation;

FIGS. 28D and 28E show bottom views of the electrode and coveringcomponents of the vacuum coagulation probe variation in FIGS. 28A to28C;

FIGS. 29A and 29B show a bottom view and a top view of another electrodevariation for an integrated vacuum coagulation probe;

FIGS. 29C and 29D show an isometric view and a side view of anotherelectrode variation; and

FIGS. 30A to 30B show a perspective view, a bottom view, a side view,and a cross-sectional view of an integrated vacuum coagulation probevariation that incorporates an offset between the active electrode andthe surface of the probe, and multiple lumens for injection of coolingor therapeutic media.

DETAILED DESCRIPTION

In light of this framework, a number of exemplary variations of theinvention are disclosed—mainly in the context of soft tissue coagulationaccomplished through less invasive approaches (e.g., thoracoscopic,arthroscopic, laparoscopic, percutaneous, or other minimally invasiveprocedures). The integrated vacuum coagulation probe variationsdisclosed herein produce intimate contact specifically between a softtissue surface and the electrode(s) or vibration elements used totransmit energy (e.g., radiofrequency or ultrasonic) capable of heatingthe soft tissue until irreversible injury is achieved making the softtissue non-viable and unable to propagate electrical impulses, mutate,or reproduce.

The integrated vacuum coagulation probe variations may also enablesupporting and/or repositioning the soft tissue during coagulation toprevent or minimize shrinking or other change in the shape of the softtissue associated with heat causing the collagen in the soft tissue todenature. Nevertheless, it should be appreciated that the integratedvacuum coagulation probe devices can be applied to other indicationsinvolving devices that are used to coagulate soft tissue where access tothe tissue is limited by a small opening into the cavity, confined spaceat the soft tissue interface, difficult to reach locations, or otheranatomic limitation.

An additional potential benefit the subject devices involves the ease ofdeployment and rapid healing post-procedure. The small incision used toaccess the soft tissue during such procedures accelerates the healingprocess and reduces the visible scar. The integrated vacuum coagulationprobe devices can be capable of being deployed through a thoracostomy,thoracotomy, median sternotomy, mini-sternotomy, mini-thoracotomy,subxyphoid access, subthoracic access, arthroscopic, or laparoscopicapproach, thereby potentially eliminating the need for long incisions toaccess the soft tissue and corresponding anatomic structures.

A need exists for integrated vacuum coagulation probe devices andmethods that create lesions of structurally strong but electricallynon-viable tissue in the atria to treat atrial fibrillation, atrialflutter, or other supraventricular tachycardia, or in the ventricles totreat ventricular tachycardia. In addition, such devices and methodscould simplify and improve other soft tissue coagulation procedures byensuring intimate tissue contact while precisely and effectively heatinga region of soft tissue. For example, tendon shrinking duringarthroscopic procedures and articular cartilage fragment removal frombony tissue are facilitated and controlled with the variations of theinvention. In addition, ablation of cancer tissue in the lung, liver,kidney, or other anatomic structure is improved by the vacuum-integratedvariations of the invention. The variations of the invention also enablepharmacologically modifying tissue structures with localizedadministration of pharmacological agents to cross-link, rendernonfunctional, destroy, remove, or otherwise adapt tissue to specificneeds.

The technology may also allow for certain procedures to be performedless invasively through limited incisions that previously requiredlarge, open incisions with inherent morbidity and risks to otheranatomic structures. As such, patients how undergo such reparative ortherapeutic surgical procedures may endure less pain, and enjoyexpedited hospital stays and shorter rehabilitative and recovery times.

The present invention relates to methods and devices that enablereliable and controlled coagulation of soft tissue during less invasiveprocedures. To accomplish this, the coagulation probe incorporatesvacuum conduits integrated with the electrode(s) and/or vibrationalelements to urge the soft tissue into intimate contact with thestrategically-located edges of the electrode(s) and/or vibrationalelements and ensure efficient transmission of energy (thermal,radiofrequency or mechanically induced ultrasonic energy respectively)capable of consistently and completely rendering a desired region ofsoft tissue electrically nonviable. The suction force pulls the softtissue into direct engagement with the electrode(s) or vibrationalelements and induces a one-sided compression of the soft tissuestructure by pulling sections of the soft tissue into the openingsdefined through the electrode(s) or vibrational elements causing softtissue residing between the openings thus over the electrode orvibrational element component(s) to compress into a smaller wallthickness.

Electrode(s) are used when applying energy to tissue (e.g., whenradiofrequency energy is transmitted into tissue, when a resistiveelectrode conducts heat energy to tissue, etc.) to cause the targetedsoft tissue to heat thereby causing cellular responses that result ininhibiting conduction of electrical stimuli through the tissue cells butmaintaining structural strength of the soft tissue. Vibrational elementsemit an ultrasonic wave as a drive shaft is used to move the vibrationalelements along the axis of the vibrational elements using a linear motoror radially around the axis using a rotary motor. This high frequency,small displacement movement causes the vibrational elements to move insuch a fashion that an ultrasonic signal is emitted into soft tissuethat is directly contacting the vibrational elements.

The integrated vacuum coagulation probe variations of the invention alsoenable passive convective cooling of the tissue surface by using thevacuum source to transport fluid along the tissue surface from a fluidsource without the need for a separate injector or pump. Convectivecooling of the surface helps avoid acute desiccation that leads tocharring, thus allowing delivery of increased energy into the tissue andcreating larger and deeper lesions by reaching maximum temperature belowthe tissue surface. The potential benefits of convective surface coolingin achieving better lesions are well known by those with skill in theart.

Supplemental or alternative to use of vacuum for passive cooling, thevacuum source may cycle the vacuum pressure applied between theelectrode(s)/vibrational elements and directly contacted soft tissue ata high rate to vary the degree of tissue compression. Such variation caninduce direct tissue vibration to develop a mechanically-inducedultrasonic wavefront capable of causing cavitation and heating of thesoft tissue for ablating the targeted tissue surface.

The integrated vacuum coagulation probe, and corresponding components,can be fabricated from at least one rod, wire, band, bar, tube, sheet,ribbon, other raw material having the desired pattern, cross-sectionalprofile, and dimensions, or a combination of cross-sections. The rod,wire, band, bar, sheet, tube, ribbon, or other raw material can befabricated by extruding, injection molding, press-forging, rotaryforging, bar rolling, sheet rolling, cold drawing, cold rolling, usingmultiple cold-working and annealing steps, casting, or otherwise forminginto the desired shape. The components of the integrated vacuumcoagulation probe may be cut from raw material by conventional abrasivesawing, water jet cutting, laser cutting, ultrasonic cutting, EDMmachining, photochemical etching, or other techniques to cut the lumens,pores, ports and/or other features of the vacuum coagulation probe fromthe raw material. Components of the integrated vacuum coagulation probecan be bonded by laser welding, adhesives, ultrasonic welding,radiofrequency welding, soldering, spot welding, or other attachmentmeans.

For several of the integrated vacuum coagulation probe variations below,various components can be fabricated from at least one wire, tube,ribbon, sheet, rod, band or bar of raw material cut to the desiredconfiguration and thermally formed into the desired 3-dimensionalconfiguration. When thermally forming (e.g., annealing) components, theycan be stressed into the desired resting configuration using mandrelsand/or forming fixtures having the desired resting shape of thepuncturing component, and heated to between 300 and 600 degrees Celsiusfor a period of time, typically between 15 seconds and 10 minutes.Alternatively, the components may be heating immediately prior tostressing. Once the volume of material reaches the desired temperature,the component is quenched by inserting into chilled or room temperaturewater or other fluid, or allowed to return to ambient temperature. Assuch, the components can be fabricated into their resting configuration.When extremely small radii of curvature are desired, multiple thermalforming steps can be utilized to sequentially bend the component intosmaller radii of curvature.

When fabricating the integrated vacuum coagulation probe components fromtubing, the raw material can have an oval, circular, rectangular,square, trapezoidal, or other cross-sectional geometry capable of beingcut into the desired pattern. After cutting the desired pattern oflumens, ports, and pores, the components can be formed into the desiredshape, stressed, heated, for example, between 300° C. and 600° C., andallowed to cool in the preformed geometry to set the shape of thecomponents, as discussed above.

Once the components are fabricated and formed into the desired3-dimensional geometry, they can be tumbled, sand blasted, bead blasted,chemically etched, ground, mechanically polished, electropolished, orotherwise treated to remove any edges and/or produce a smooth surface.

Holes, slots, notches, other cut-away areas, or regions of groundmaterial can be incorporated in the components to tailor the stiffnessprofile or incorporate features that enhance performance of the devices.Cutting and treating processes described above can be used to fabricatethe slots, holes, notches, cut-away regions, and/or ground regions inthe desired pattern to taper the stiffness along, focus the stiffnessalong the length of, reinforce specific regions of, or otherwisecustomize the stiffness profile of the vacuum probe components.

Naturally, any number of other manufacturing techniques may be employed.Furthermore, it is to be understood that the exemplary deviceconfigurations may be varied.

Vacuum-Integrated Coagulation Probe Variations

FIG. 1A illustrates a variation of a coagulation device consisting of aprobe 2 and a handle 102 (showing a cross-sectional view of the handlebody). In this variation, the probe 2 includes a shaft 4 having ahousing 9 at a distal section 5 of the shaft 4. Variations of thecoagulation device may employ any variety of shapes and sizes for thehandles. In the example shown, the handle 102 includes a plurality ofconnectors 21, 22, 23 for connecting the probe to a power supply 60, afluid source 55 and a vacuum source 50 respectively.

In a variation of the device, the fluid source 55 connection 22incorporates a flow limiter to keep the perfusion rate through theperfusion lumen constant at different vacuum pressures and positions ofthe fluid source. In one example, the flow limiter comprises a constantdiameter tubing that restricts flow therethrough along a large range ofvacuum pressures or fluid source injection pressures. For example, apolyimide tubing having a 0.006″ ID, 0.350″ length, and a 0.003″ wallthickness is capable of limiting the perfusion rate to 4 ml/min throughthe perfusion lumen despite vacuum pressures ranging from −200 mmHg to−600 mmHg.

Most variations of the devices described herein include a connector fora power supply and vacuum source. However, such connectors may becombined in a single connection and locked to the handle. Combining thevacuum and fluid source connectors into a single componentinterconnected by a bridge designed to provide stability ensuresintegrity of the connectors while rotating the mating connector intoengagement or removing the mating connector. Alternatively, the devicemay include more connectors than that shown in FIG. 1A.

As illustrated, the shaft 4 may optionally include additional components(such as a strain relief 24) to increase the robustness of the device.The shaft 4 includes a housing 3 located at a distal end 5 of the shaft4. As discussed below, the housing 3 includes an element 8 and anopening that expose the element 8 to tissue. The element 8 may be anelectrode or vibration element as discussed herein. In the variationshown in FIG. 1A, the housing includes a lip 9 around at least a portionof the opening (in this case around the proximal and distal ends of theopening). The lip 9 includes a free portion 11 that is unattached to thehousing 3. The free portion 11 of the lip 9 conforms to tissue whenplacing the housing 3 over an un-even surface. This feature improves theability of the housing 3 to form a seal against tissue while drawingtissue into the opening to contact the element. The end of the housing 3includes an opening for a tether 42 (a suture, vessel loop, combinationof vessel loop and suture, or other similar structure may be substitutedfor the tether 42 for convenience, the term tether shall refer to any ofthese or similar structures). The tether 42 assists in directing thedevice to an intended site. Although the illustrated example shows asingle tether 42, variations of such devices may include two or moretethers 42 to aid in manipulation of the device.

FIG. 1B shows a side view of a distal end of the shaft 4 having thehousing 3. Typically, the shaft 4 comprises a multi-lumen tube orextrusion. In the present example, the shaft 4 comprises a three lumenextrusion. The housing 3 also includes an opening (not illustrated) on abottom portion where the opening exposes an element (also notillustrated).

In use, the practitioner applies suction to the main lumen. The suctiondraws tissue within the opening, causing contact between the tissue andthe element. As noted herein, the probe 2 is useful in creatingcoagulation lines around soft tissue. However, because the probe 2 maybe advanced in contact with irregular tissue surfaces, curvature of theelongate housing 3 may prevent the formation of a vacuum when theopening is not flush against tissue. To address this situation, theprobe includes one or more lips 9. The lip 9 may encircle the entireopening or may be located around a portion of the opening. The lip 9includes a free portion 11 to increase the ability of the opening toform a seal about the tissue. The free portion 11 of the lip 9 providesan increased surface area that is able to flex independently of thehousing 3. Accordingly, the free portion 11 of the lip 9 allows portionsof the housing 3 to be spaced from the tissue surface without breakingthe vacuum generated by the probe 2.

FIG. 1B also shows a tether extending from the housing 3 in a distaldirection. The tether is useful to advance the probe around organs.Moreover, the use of two or more tethers may allow “back and forth”manipulation of the housing by pulling alternatively on each tether. Thedesign of the illustrated probe 2 provides a tether 42 that is integralto the housing 3. Such a feature reduces the size of the connectionbetween the tether 42 and the housing 3 by eliminating the need for aknot or other fastening means to join a tether to the probe.

FIG. 1C illustrates a side-cross sectional view of a probe 2. Asillustrated, the elongate shaft 4 contains an elongate housing 3. Thehousing 4 includes an element 8 within the housing 3, where the element8 is exposed at the bottom of the housing 3 via an opening 10 in a sidewall. In this variation, the element 8 is located within the main lumen6. A perfusion lumen 16 extends above and parallel to the main lumen 6directly opposite to the opening. As shown in FIG. 1D, thisconfiguration minimizes a width of the housing 3.

Typically, the fluid delivery lumen (or perfusion lumen) 16 is in fluidcontact with the element 8 such that fluid may be delivered to theelement and tissue while a suction is applied through the main lumen 6.This action causes tissue to be drawn in to the opening 10 and incontact with the element 8 while the fluid passes over the element andtissue.

FIG. 1E shows a bottom view of the probe 2 of FIG. 1C illustrating theopening 10 in a side wall of the housing 3 that exposes the element 8.In addition, in the illustrated variation, lips 9 are located around theopening 10 where the proximal and distal ends of the opening 10 includelips 9 with free portions 11.

FIGS. 1C and 1D illustrate the housing 3 as further including a spinemember 218. The spine member 218 may provide column strength for theprobe 2 and/or housing 3. In some variations of the device, the spinemember 218 is elastic or resilient. Alternatively, the spine member 218may also be malleable, or shapeable to permit shaping of the elongatehousing 3 and element 8 for creating coagulation lines having apredefined pattern.

FIG. 1F illustrates a partial view of a spine member 218 connected to atether 42. The spine member 218 is secured to the tether 42, whichensures that the tether is affixed within the housing. As illustrated inFIG. 1G, variations of the tether 42 may include a section of increaseddiameter to further assist in retaining the tether within the body.

FIG. 1H illustrates an example of an element 8 coupled to a conductingmember or wire 13. In this variation, the wire 13 extends through theshaft (not shown) to connect the element 8 to the power supply.Furthermore, the element 8 may optionally include a coagulation sleeve27. The coagulation sleeve 27 may be used as reinforcement for theelement 8. The coagulation sleeve 27 may also serve as a return elementsuch that when tissue contacts the element 8 and coagulation sleeve 27the tissue completes a circuit allowing current to flow into through thetissue thus coagulating the tissue.

As noted above, variations of the coagulation probe 2 include shapeablespine members that permit the shaft and or housing member 3 to form aspecific shape. FIGS. 1-1K illustrates some examples of suchconfigurations. As shown in FIG. 1, the elongate housing member 3 mayform a partial “C” shape. FIGS. 1J to 1K illustrate yet anothervariation of the probe 2 in which a single probe includes a branchedshaft or elongate housing 2 to produce a probe 2 with dual housings 3and element s. FIG. 1J shows a variation in which both elongate housingmembers 3 form similar curved shapes. Such a configuration may be usefulwhen trying to coagulate around vessels or other body structures. FIG.1K illustrates another variation in which both elongate housing members3 form curved shapes. However, in this variation, the distal ends of theelongate housing members 3 are offset. Such a configuration is useful toavoid pinching of the vessel or body structure as the elongate members 3assume the curved shape. For example, the elongate members shown mayassume the curved shape via insertion of a stylet into the main lumenwhere the stylet has a pre-shaped curve.

FIG. 2A shows a perspective view of another variation of a probe housing3. In this variation, the main lumen 6 extends through a top portion ofthe housing. The main lumen 6 can be used to provide fluids (e.g., viause of a fluid delivery lumen—not shown). The opening 10 is on thebottom of the housing 3 and contains the element (not shown). As notedabove, the main lumen 6 (and any fluid delivery lumen) are in fluidcommunication with the element to allow simultaneous application of avacuum and irrigation to the tissue adjacent to the housing 3. Thehousing 3 includes a lip 9 having a free portion 11 to assist in sealingthe device against tissue. Use of this configuration, in which a singlelumen runs along the top of the housing 3 allows the ease ofincorporating a steering mechanism (as described herein) within theelongate housing 3.

FIG. 2B shows a side cross-sectional view of the housing 3 of FIG. 2A.As shown, the main lumen 6 is located on a top portion of the housing 3while the perfusion lumen (not shown) is parallel to the main lumen 6.Both lumens are opposite to the opening 10 in a sidewall of the housing3. In this variation, the element (not shown) is affixed within aseparate cavity 17 that is in fluid communication with the main lumen 6and perfusion lumen. The illustrated variation also includes a lip 9having a free portion 11 to assist in formation of a seal againsttissue.

FIG. 2C illustrates another variation of a probe 2 that is similar tothat shown in FIGS. 2A to 2B. In this variation, there is a single mainlumen 6 in a top portion of the housing 3. The main lumen 6 and cavity17 are in fluid communication at the distal end of the housing 3. Aseparate fluid perfusion lumen 16 advances through the main lumen andinto the proximal portion of the cavity 17. This configuration allowsdelivery of fluid at one end of an element 8 while aspiration isprovided at the other end. The resulting action is the creation of avacuum at the opening 10 and against tissue while fluid from the fluiddelivery lumen 16 passes over the tissue and element 8. Although notshown, electrical connection for the element 8 may be passed through themain lumen 6. Furthermore, the shape of the elongate housing 3 maypermit ease of positioning.

FIG. 2D shows a bottom view of the probe 2 of FIG. 2C. As shown, theperfusion lumen 16 extends to a first side of the element cavity 17while the main lumen 6 terminates at an opposite side of the electrodecavity 17. Furthermore, the shape of the housing 3 containing the mainlumen 6 may be circular to ease positioning of the housing 3.

FIGS. 2E-2L show another aspect for use with the probes 2 describedherein. In this aspect, the probe 2 configuration accommodates a track300. The track 300 may be any guide type member that operates as a trackor rail for navigation, steering, or shaping of the probe 2. The track300 includes a variety of devices such wires, steerable catheters,steerable guide-wires, shaped tubes or mandrels, etc. (where such guidedevices will be referred to as “track” or “rail). Optionally, the track300 may be keyed, have a groove, or have any other feature that permitsmaintaining the orientation of the track 300 with the probe 2.

FIG. 2E illustrates a partial cross-sectional view of a probe 2 having atrack 300 extending through a housing 3. In this variation, the probe 3can include a track tubing 274 having a track lumen 276 foraccommodation of the track 300. In certain variations of the probe 2,the track lumen 276 is fluidly isolated from other portions of the probe2 and/or housing 3. For example, it may be desirable to fluidly separateisolate the track lumen 276 from fluid flow in a perfusion lumen 16,vacuum lumen 6, main cavity 17, shaft (not shown) or other portion ofthe device 2. Fluidly isolating the track lumen 276 provides a number offunctional benefits such as preventing passage of current to the track300, maximizing vacuum at an opening 10 of the housing 3, preventingperfusing fluid from escaping through the distal end of the probe 2.However, it is understood that variations of the probe 2 include use oftrack lumens that are not fluidly isolated from the remainder of thedevice. Moreover, in additional variations of the probe 2, a track lumen276 may be integral with the housing 3 or shaft of the probe 3 and maynot require the use of a separate track tubing 274.

Although not shown, the variation of FIG. 2E may include any number ofopenings in the top of the housing 3. Such openings can allow forincreased flexibility of the probe housing. In such a case, theperfusion lumen serves to function as the track lumen.

FIG. 2F illustrates a magnified view of section 2F from FIG. 2E. Asshown, the track 300 extends through the track lumen 276 and through adistal end of the probe housing 3. In this example, the track tubing 274extends through the perfusion lumen 16 of the probe 2. Accordingly, oneor more channels 280 can be used to fluidly couple the perfusion lumen16 to the main cavity 17. A separate channel 282 can be used to allowthe track lumen 276 to exit the device. While the channels 280, 282 maybe integrally formed with the housing 3, a simpler alternate approachmay include the use of a plug 278.

FIGS. 2G to 2I show variations of plugs 278 for use as described above.It is understood that any number of variations of such a plug are withinthe scope of the invention. The illustrated plugs 278 are rotated tomore clearly illustrate a first channel 280 that allows for fluidlycoupling a perfusion lumen to the main cavity of the probe. A secondchannel 282 extends through the plug 278 to allow passage of the tracklumen. Such plugs 278 can provide additional structural improvements forthe probe. For example: the second channel 282 can be sized to closelyfit any track tubing and/or serve as a location for an adhesive toretain the track tubing; the plug 278 can isolate the perfusion fluidfrom exiting the device at the distal end; the plug 278 can also act asa strain relief against the track 300 and prevent inadvertent cutting ordamage to the housing by the track; etc.

FIG. 2J illustrates a partial cross sectional view of another variationof a probe 2 having a track 300 extending through a housing 3. In thisvariation, the track 300 extends through a vacuum or main lumen 6 andmain cavity 17 rather than through the perfusion lumen 16. Thisvariation may or may not use a track tubing 274.

FIGS. 2K to 2L show one example of a method of using a probe 2 with arail 300 and rail lumen. As shown in FIG. 2K, a track 300 is placedproximate to tissue or the area to be treated. Although a track 300 maybe used by itself, the track 300 may also be used with or be a part ofan access device 182. Examples of such access devices may be found in:U.S. Patent Provisional Ser. No. 60/726,342, filed Oct. 12, 2005,entitled “Diaphragm Entry for Posterior Access Surgical Procedures”;U.S. patent application Ser. No. 11/408,315, filed Apr. 21, 2006,entitled “Diaphragm Entry for Posterior Surgical Access”; U.S. patentapplication Ser. No. 11/408,307, filed Apr. 21, 2006, entitled“Diaphragm Entry for Posterior Surgical Access”; U.S. patent applicationSer. No. to be assigned, filed on the same day as this application,entitled “Diaphragm Entry for Posterior Surgical Access”, (AttorneyDocket No. NCNT-N-Z006.01-US), the entirety of each of which is herebyincorporated by reference.

In addition, while the track 300 is shown as forming a loop, the track300 may form any open or close shape or profile whether 2 dimensional or3 dimensional as required by the particular procedure. For example, thetrack 300 may be a shapeable or pre-shaped mandrel that forms an open“J” type profile. In another example a track 300 may have a 2dimensional shape but through manipulation by the surgical practitioner,the track 300 and probe 2 may conform to the surface of the tissue beingtreated.

FIG. 2L shows a probe 2 advancing over the track 300 and conforming tothe profile of the track 300 As noted herein, when properly positioned,the probe 2 may apply suction to engage the tissue against the probe'selement. The probe 2 simultaneously, or sequentially, apply a perfusingfluid to the area being treated.

FIGS. 3A to 3C illustrate another variation of a vacuum probe 2. FIG. 3Aillustrates a side view of a housing 3 of the vacuum probe 2 located atthe end of a shaft 4. As described herein, the housing 3 of the probewill be flexible to accommodate maneuvering of the probe 2 to the siteand to conform to tissue surfaces for formation of a seal. In thisvariation, the elongate housing 3 includes a lip 9 around an opening 10where the lip 9 has a free portion 11 at a proximal end of the opening.However, variations of the device include an opening having the free endof the lip extending around the perimeter of the opening.

FIG. 3B illustrates a bottom view of the probe 2 of FIG. 3A. The housing3 comprises an opening 10 in a sidewall to expose two pairs ofelectrodes 8. Such a combination may be used to map electrical pathwayswithin tissue to determine the proper areas to form coagulation lines.The electrodes 8 can be affixed to the shaft 4 within a main lumen 6 ofthe housing 3. Moreover, the shaft 4 may have a lumen in fluidcommunication with the main lumen 6 such that when coupled to a vacuumsource, the opening 10 and lip 9 forms a seal against tissue drawing thetissue into contact with the electrodes 8.

FIG. 3C shows a top view of a handle 102 for use with the probe of FIGS.3A and 3B. In this variation, because the probe 2 is useful for mapping,the handle 102 comprises a connector 21 for a power supply 60 and avacuum connector 23 for coupling the device 2 to a vacuum source 50.Though not shown, variations of the device include a handle 102 with anadditional fluid supply connector.

FIG. 4A illustrates a sample probe 2 having multiple tethers 42 attachedto the distal end of the housing 3. As noted herein, the multipletethers 42 permit a manipulation of the housing 3 by alternativelypushing and pulling on either tether 42.

FIG. 4B shows a curved or shapeable stylet 25 as mentioned herein. Whenused, the stylet 25 is typically inserted into the main lumen to shapethe distal end of the probe into a desired shape. In some variations,the stylet 25 will be flexible and the shaft of the probe sufficientlyrigid such that the does not affect the shape of the probe until itreaches the housing portion. Alternatively, or in combination, a varietyof steerable members may be used in place of the stylet.

Variations of shaft 4 described herein may be fabricated from a polymersuch as PEBAX®, polyester, polyurethane, urethane, silicone, polyimide,other thermoplastic, thermoset plastic, or elastomer. Alternatively, theshaft 4 may be a metal (e.g., titanium, etc.), or metal alloy (e.g.,stainless steel, spring steel, nickel titanium, etc.) fabricated as acut tube, braided wires, a mesh, one or more helically wound wires, orother configuration encapsulated in or covered by a polymer. When usingpolymer coverings/insulation 7 over tissue heating electrode(s) orvibrational element(s) 8 and/or the shaft 4, the covering/insulation 7may be extruded, injection molded (especially when incorporatingdiscrete features such as the opening without requiring another step ofcutting the covering/insulation around the defined electrode,vibrational element), dipped, or applied using another manufacturingprocess involving embedding or covering the electrode, vibrationalelement, and/or shaft support structures with the polymer covering.

As discussed herein, the element 8 may comprise an electrode or avibrational element. When transmitting radiofrequency energy in unipolarfashion between at least one electrode 8 and a large surface area, areference electrode (not shown) is placed on the subject's body remotefrom the electrode 8 and a single wire is routed to each electrode andconnected to a radiofrequency generator 60. When transmitting D.C. orradiofrequency energy in bipolar fashion between pairs of electrodes 8,individual wires are connected to each of two or more individual,closely-spaced electrodes 8 and RF or DC energy is applied between theelectrodes using a radiofrequency or direct current generator 60.

When utilizing resistive heating of the electrode 8 and relying onconduction to transfer heat to contacted tissue, wires are connected toeach electrode 8 (e.g., resistive element in this case) separated by alength defining the region to be heated so the tissue contacting lengthof the electrode 8 heats to the desired temperature and the heat isconducted to contacted tissue. In a resistive heating approach, theelectrode(s) may advantageously be constructed from Nichrome wire orother stock material as this material is commonly used in resistanceheaters.

When mechanically vibrating the vibrational element(s) 8 axially orradially at a high rate (e.g., 5 kHz to 1 MHz and preferably 15 kHz to30 kHz) and small displacements (preferably <1 mm in each direction),vibrational element(s) 8 are connected to a drive shaft that is coupledto a linear motor 70 or a rotary motor 80 that causes the cyclicmicro-displacement and invokes an ultrasonic signal from the movement ofthe vibrational element(s) 8 relative to the contacted soft tissue. Theultrasonic signal propagates through the soft tissue structures causingcavitation that induces heating of the soft tissue and renders the softtissue electrically nonviable.

Temperature sensors may be associated with each electrode/vibrationalelement 8 with temperature sensor wires routed along the shaft to thehandle where they are connected to another electrical connector capableof transmitting the temperature signal to a radiofrequency generator 60with temperature monitoring or control capabilities or a separatetemperature monitor. U.S. Pat. No. 5,769,847, entitled “Systems andmethods for controlling tissue ablation using multiple temperaturesensing elements” which is incorporated herein by reference, describestissue coagulation systems utilizing multiple electrodes and temperaturesensors associated with each electrode to controllably transmitradiofrequency energy and maintain all electrode(s) essentially at thesame temperature. The vacuum coagulation probe electrode(s) orvibrational element(s) and associated temperature sensors may beconnected to such a mechanism to control transmission of radiofrequencyor mechanically-induced ultrasonic energy to each electrode/vibrationalelement to control the heating of contacted soft tissue.

Variations of the integrated vacuum coagulation probes described hereinexposes electrode/vibrational element 8 only along one side of thevacuum-integrated coagulation probe and insulates the opposite sideagainst transmission of radiofrequency or ultrasonic energy, and heat tocollateral, non-targeted tissue structures

These openings 10 enable producing a vacuum attachment with the probe 2against the soft tissue throughout the length of electrode(s) 8, therebyensuring intimate and direct tissue contact between theelectrode(s)/vibrational element(s) 8 and the soft tissue. The openings10 also orient the edges of the electrode(s)/vibrational element(s) 8,commonly associated with high current densities (when usingradiofrequency energy) transmitted into the soft tissue, to create acontinuous, consistent lesion throughout the length of the electrode(s)8 without producing hot spots that interfere with creating lesionshaving consistent depth and width. The combination of creating intimatetissue contact and directing the current density profile createscontrolled and efficient heating of the soft tissue required whencoagulating tissue to produce defined lengths of transmural lesions inatrial tissue (or other soft tissue).

When using mechanically-induced ultrasonic energy, the openings 10define edges along the electrode(s)/vibrational element(s) 8 thatproduce friction as the vibrational elements move relative to the softtissue surface and cause vibration of the soft tissue and surroundingfluid which induces an ultrasonic waveform that propagates throughoutthe soft tissue causing cavitation that results in heating of the softtissue. The pore(s)/opening(s) 10 may have a constant width or varyalong the length of the electrode/vibrational element 8 to adjustcontact forces throughout the length of the electrode(s)/vibrationalelement(s) 8.

The vibrational element(s) 8 may be moved via a drive shaft that iscoupled to a linear motor for axial displacement or a rotary motor forradial angular displacement (each, referenced above). When utilizing alinear motor to induce the displacement of the vibrational element(s)relative to the soft tissue, the windings are advantageously orientedsubstantially perpendicular to the probe axis or at an acute angle fromthis perpendicular plane to enhance the transmission of high frequencymechanical displacement into ultrasonic propagation waves capable ofcausing cavitation of soft tissue and the resulting heat. When utilizinga rotary motor to induce angular displacement of the vibrationalelement(s) relative to the soft tissue, the windings are advantageouslyoriented substantially parallel to the probe axis or at an acute anglefrom the probe axis.

The electrode(s)/vibrational element(s) 8 may be fabricated from metal(e.g., tungsten, titanium, tantalum, platinum, gold, silver), metalalloy (e.g., stainless steel, spring steel, nickel titanium, platinumiridium, silver chloride, etc.), metals deposited over a carrier (e.g.,gold-plated stainless steel, gold deposited polyimide, platinumdeposited polyester, etc.) or a combination of materials fabricated,with methods described previously, to define the shape, the coil/windingwidth B, the coil pitch A (e.g., as shown in FIGS. 28A, 28C) orseparation/gap (for non-helical configurations as shown in FIGS. 29A to29D), shaft 4 attachment features (e.g., threads, slots, etc.) or otherfeatures. The electrode(s)/vibrational element(s) 8 may be fabricatedfrom elastic or superelastic conductive materials so they can bedeflected upon exposure to an external force (e.g., actuation of thevacuum, manual bending, etc.). Alternatively, they may be fabricated andtreated such that the electrode(s)/vibrational element(s) 8 is/aremalleable so the operator may tailor the electrode(s)/vibrationalelement(s) 8 to the anatomic structures. Similarly, the shaft 4,described above, may be adapted to be malleable.

The perfusion tube 100 or lumen 16, disclosed herein, can serve multiplefunctions. The perfusion tube 100 or lumen 16 may be fabricated from amalleable metal or alloy to enable the operator to impart a shape to thedistal section 5 that contains the electrode/vibrational element 8and/or shaft 4 and maintain that shape during placement and/orcoagulation. Alternatively, the perfusion tube 100 or lumen 16 may befabricated from a polymer tube or a braided polymer tube, or be integralto or embedded into the covering/insulation using an injection moldingor extrusion process that defines a separate lumen. Stylets havingdiscrete shapes and/or malleability may be inserted through theperfusion tube 100 or lumen 16 to adjust the shape of the probe duringplacement or coagulation. Alternatively, a separate steering mechanismmay be inserted through the perfusion tube 100 or lumen 16 to remotelymaneuver the probe. Such remote manipulation features are especiallyrelevant during less invasive procedures. The perfusion tube 100 orlumen 16 incorporates at least one outlet, aperture, or cut-out 26 alongthe distal end and is routed to a port at the handle 102 of the probe toenable passive fluid cooling of the tissue during lesion creation. Thesuction force applied by a vacuum source 50 through the shaft vacuumlumen 6 may be used to pull fluid (e.g., saline, Ringer's solution,plasmalite, etc.) from a fluid source 55 (e.g., saline bag) through theperfusion tube 100 past the distal outlets, or cut-outs 26 and along thelumen 6 of the probe conducting heat away from the soft tissue surfacedirectly engaged against the electrode/vibrational element 8. Theknown/constant diameter and length of the perfusion tube 100 or lumen 16combined with the known/constant pressure applied through the probe(e.g., −200 mmHg to −1400 mmHg; preferably −400 to −600 mmHg) will thenproduce a constant fluid perfusion through the probe without the needfor a separate pump/injector.

The principle factor considered important in the improvement in thelesion creation capability observed in these integrated vacuum probevariations is the integration between the electrode/vibrational element8 and the vacuum coupling 6. In the variations of the invention, thevacuum source 50 applies suction directly through openings 10 in theelectrode(s)/vibrational element(s) 8 to force soft tissue directly incontact with the electrode(s)/vibrational element(s) 8. As opposed toalternative, inferior approaches which contain suction means andablation structures that are independent and separated where suction isapplied to tissue adjacent to and separate from tissue that contacts theelectrode, by applying suction to soft tissue directly contacting theelectrode/vibrational element 8 according to variations of theinvention, the soft tissue is forced into the openings 10 betweenwindings of the electrode(s)/vibrational element(s) 8 and intoengagement with the electrode(s)/vibrational element(s) throughout thelength consistently. Furthermore, variations of the present inventionmay tailor the pitch (A) and winding width (B) so the probeelectrode/vibrational element 8 contacts the soft tissue at spacedintervals (either consistent or varied) thereby optimizing the currentdensity profile (when transmitting RF energy) or the vibrationalwaveform (when mechanically inducing ultrasonic energy) along the lengthof the electrode/vibrational element and reducing the disparity incurrent density or ultrasound waveform observed throughout the length ofthe conventional ablation probes. These factors enable the variations ofthe invention to create consistent lesions having defined dimensionswithout the need for several lesion monitoring tools (e.g., temperaturesensors, etc.).

FIGS. 5A and 5B show an assembled vacuum-integrated coagulation probe 2.FIGS. 6A to 6F show the distal section 5 of the vacuum-integratedcoagulation probe 2 in FIGS. 5A and 5B. The assembled vacuum-integratedcoagulation probe incorporates a distal section 5 that comprises atleast one electrode/vibrational tissue heating element 8 encapsulated ina covering 7 that has an aperture 20 along a segment, that exposes theconductive windings and openings 10 between winding that are coupled tothe vacuum lumen 6, which defines the electrode/vibrational element 8.The electrode/vibrational element 8 provides structural integrity of thedistal section 5 while defining a central vacuum lumen 6 and openings 10between individual, separated windings. The distal section 5 is coupledto a handle 102 by a shaft 4 that comprises an extension of theelectrode/vibrational element 8 or a tubular (single or multiple lumen)member containing electrical wires or a drive shaft that are secured tothe electrode/vibrational element 8 and routed to an electricalconnector or mechanical coupler at the handle. A vacuum port that iscoupled to the vacuum lumen 6 is connected to a vacuum source 50. Afluid perfusion port is coupled to the perfusion tube/channel 100 and isconnected to a fluid source 55. The electrical wires (for variationsinvolving transmission of radiofrequency energy) are connected to aradiofrequency generator 60. For variations involvingmechanically-induced ultrasonic energy, the drive shaft is coupled to alinear motor 70 or rotary motor 80 that imparts high frequency, smalldisplacement cyclic movement of the drive shaft thus the vibrationalelement relative to contacted soft tissue.

As shown in FIGS. 6A to 6F, this example of a vacuum-integratedcoagulation probe 2 comprises a dual lumen tubing fabricated from anon-conductive polymer 7 extruded or injection molded into a dual lumentubing having a side wall with at least one aperture 20, a distal tipthat caps the distal end of the lumens 6 and 16 and defines an opening40 through which another separate tubing, tape, or suture can be securedto manipulate the probe; and an electrode/vibrational element 8partially encapsulated in or otherwise secured to the dual lumen tubing.The at least one electrode/vibrational tissue heating element 8comprises at least one pore or opening 10 coupled to the first lumen 6of the multilumen tubing, as shown in FIGS. 6A to 6F. The fluidperfusion tube 100 (which may also function as a channel for inserting asteering mechanism or preshaped stylets that enable maneuvering thedevice) defines a lumen 16 that is coupled to the vacuum lumen 6 throughan outlet 26.

As shown in FIGS. 6A to 6F, the perfusion lumen 16 defined by themulti-lumen tubing routes fluid from a fluid source 55 through a fluidperfusion port at the handle, through a outlet 26 between the fluidperfusion lumen 16 and the vacuum lumen 6, along theelectrode/vibrational element 8, along the proximal region of the shaft4, and through a vacuum port at the handle, and to the vacuum source 50to enable hydrating and fluid cooling of soft tissue contacting theelectrode/vibrational element 8. Perfusion of fluid through themultilumen vacuum probe enables cooling soft tissue during coagulationto enable transmitting more energy into the soft tissue therebyconducting the heat further into the tissue and creating deeper lesions.

FIGS. 7A through 7I show an alternative multilumen vacuum-integratedcoagulation probe 2 variation. FIGS. 7A to 7D show an isometric view, abottom view, a side-sectional view, and a side view of the multilumenvacuum-integrated coagulation probe 2. FIGS. 7E to 7I showcross-sectional views of the probe. As shown in FIGS. 7B, 7C, 7G, and7H, this vacuum-integrated coagulation probe 2 variation incorporatesribs 30 that reinforce the covering 7, especially at the aperture 20 inthe covering 7, without blocking a substantial cross-section of thevacuum lumen 6 (as shown in FIGS. 7G and 7H). These ribs 30 maintainseparation between opposing sides of the covering 7, especially alongthe aperture 20, as the distal section 5 of the probe 2 is deflected orpositioned into curved shapes. In addition, the ribs 30 do not interferewith the ability of the electrode/vibrational element 8 that is exposedthrough the aperture 20 to contact soft tissue. As such, the ribs 30ensure the aperture 20 maintains it's geometry where the width C of theaperture exceeds the offset D between the plane of the aperture to thesurface of the electrode/vibrational element to ensure soft tissue isforced into the aperture and into contact with the electrode/vibrationalelement as vacuum is applied from a vacuum source 50 to the vacuum lumen6. The number and/or width of the ribs may be varied as well as theirgeometry. However configured to avoid interference as discussed above,the purpose of the ribs, braces or struts 30 is to limit or preventeither one or both of outward buckling of the covering wall when bendingor otherwise manipulating the body, or wall collapse (laterally and/orvertically) once a vacuum seal has been established between tissue andthe device.

FIGS. 27A to 27C show an exploded view, a side view, and a close-up viewof another integrated vacuum coagulation probe 2 variation of theinvention. Probe 2 incorporates a shaft 4 that defines a lumen 6, asshown in FIG. 27A.

Shaft 4 shown in FIGS. 27A to 27C comprises of a polymer, such as listedabove, covering or encapsulating a rectangular (or elliptical orcircular, etc.) wire wound into a helix (alternatively, a mesh,intersecting helices, or other configurations of windings can beutilized) throughout a majority of the probe length with a section ofthe polymer removed to create an aperture 20 through which the suctionpore(s) or opening(s) 10 between windings of electrode/vibrationalelement 8 are coupled to lumen 6, and the conductive surface ofelectrode/vibrational element 8 is exposed.

As such, the inventive variation in FIGS. 27A to 27C comprises avacuum-integrated coagulation probe fabricated from four components: 1)a fluid perfusion tube 100 that incorporates at least one aperture 26 atits distal end; 2) an electrode/vibrational element 8 and integral shaftsupport coil connected to a small diameter electrical conduit or alarger diameter drive shaft 12 that contains sufficient column strengthto rapidly move the electrode/vibrational element axially or radially;3) a shaft 4 and a covering 7 that defines at least one aperture 20along the electrode/vibrational element 8 and coupled to the opening(s)10 between windings of the electrode/vibrational element 8; where theshaft 4 is connected at the handle 102; and 4) a handle 102 that housesat least one electrical connector 14 for electrodes, or at least onemechanical coupler 14, for vibrational elements, and ports that couplethe lumen 6 of the shaft 4 to a suction device 50 and the lumen of thefluid perfusion tube 100 to a fluid source 55. The electricalconnector/mechanical coupler 14 is routed to a radiofrequency or directcurrent generator 60, when energy is transmitted to electrodes, or amechanical vibration mechanism (e.g., linear motor 70 or rotary motor80), when mechanically-induced ultrasonic energy is transmitted tovibrational elements. Alternatively, the section of the probe containingthe exposed segment of the electrode/vibrational element 8 and thecut-out region(s)/aperture(s) 20 of the covering 7 that exposes thesuction pore(s)/opening(s) 10 through the electrode(s)/vibrationalelement(s) 8 may be fabricated from one or more separate component(s)than the shaft.

The shaft 4 and/or distal section 5 of the probe housing theelectrode/vibrational element 8 and suction pore(s)/opening(s) 10 mayhave a circular cross-section, elliptical cross-section, rectangularcross-section, or other geometry depending on the stiffnessrequirements, access characteristics, and other considerations. Theshaft 4 may be fabricated as a single lumen tubing as shown in FIGS. 27Ato 27C or alternatively multi-lumen tubing having two or more separatelumens serving specific functions. At its proximal end, a portion of theshaft 4 is bonded to a handle 102 that optionally incorporates at leastone port that feeds the shaft lumen(s) 6 and the lumen 16 of theperfusion tube 100. The port(s) may incorporate luer adaptor(s) or othertubing connector(s) to facilitate attaching IV tubing, surgical tubing,or other tube capable of connecting to a vacuum source 50.

The handle 102 may also house at least one electrical connector ormechanical coupler 14 to which the electrical wire(s) or drive shaft(s)12 are attached at the proximal end. The wire(s) or drive shaft(s) 12will then be routed to the electrode(s) or vibrational element(s) 8 toenable transmitting energy (radiofrequency, or mechanically-inducedultrasonic energy respectively in these examples).

In the variation in FIGS. 27A to 27C, the helical wire functions both asan electrode or vibrational type tissue heating element 8, and thesignal wire or drive shaft 12. When the electrode or vibrational elementis not integral to the shaft, discrete signal wire(s) or drive shaft(s)12 are typically secured to the electrode or vibrational element 8 andare routed to the electrical connector or mechanical coupler 14,respectively, at the handle 102.

As shown in FIGS. 27A to 27C, at least one aperture 20 is created alongone side of the coagulation probe through the side wall of thecovering/insulation 7 to expose the conductive surface of the conductivewindings 8 and pores/openings/gaps 10 between windings, and coupling thelumen 6 of the shaft 4 to the exposed surface of the helical wirethereby defining the integrated electrode(s)/vibrational element(s) 8.

FIGS. 28A to 28C show the distal section 5 of another vacuum coagulationprobe 2 variation used to coagulate soft tissue during open surgicaland/or minimally invasive access (e.g., thoracoscopic, endoscopic,arthroscopic, laparoscopic, or other approach) into the body cavity.FIGS. 28D and 28E show two components (the electrode/vibrational element8 and the covering or insulation 7 over the electrode/vibrationalelement) of the vacuum coagulation probe in FIGS. 28A to 28C. FIG. 28Dshows the cut tube that defines conductive windings of theelectrode/vibrational element 8 and in this configuration the support ofthe shaft 4 with a lumen 6 therethrough. FIG. 28E shows thecovering/insulation 7 that overlays or covers the cut tube andincorporates an aperture 20 that exposes the electrode/vibrationalelement 8 and openings 10 between windings of the electrode/vibrationalelement 8. The covering/insulation extends along the shaft 4 of theprobe and terminates at the handle.

The integrated vacuum coagulation probe 2 variation in FIGS. 28A to 28Eincorporates a flexible polymer shaft 4 that has a side wall, and coversor encapsulates an electrode/vibrational element 8 fabricated from a cut(laser cut, waterjet cut, chemically etched, etc.) tube (e.g., metal oralloy). The cut tube incorporates an uncut distal tip extending intowindings cut into the raw tubing having a pitch (A) and width (B). Thepitch (A) is the center-to-center distance between windings. Thewindings extend a length coincident with the electrode/vibrationalelement 8 that is defined by exposing the conductive surface of thewindings and the openings 10 between windings to tissue by at least oneaperture 20 in the side wall of the covering/insulation of the shaft 4.The cut tube may extend further beyond the at least one aperture 20 inthe covering that defines the at least one electrode/vibrational element8 such that the cut tube continues along the entire shaft terminating atthe handle attachment point.

Alternatively, the cut tube may be limited to the electrode/vibrationalelement 8 region and terminate just past the aperture 20 of thecovering/insulation 7; this dedicated cut tube electrode/vibrationalelement 8 is then secured to a separate shaft 4. The inner diameter ofthe shaft is advantageously greater than or equal to the inner diameterof the electrode/vibrational element region to optimize the suctionforce applied along the opening and prevent tissue that is pulled intothe electrode/vibrational element lumen from lodging in the shaft lumen.In the continuous winding (integral electrode/vibrational element andshaft) configuration, the electrode/vibrational element and shaftsections of the cut tube are covered or encapsulated by an insulativepolymer 7 with an aperture 20 in the side wall of the polymer coveringto define the electrode/vibrational element 8.

The winding configuration in this configuration may incorporate a singlepattern of windings or adjust the pitch, winding width, and/or cut tubegeometry from the electrode/vibrational element 8 region to the shaftregion. In the separate electrode/vibrational element and shaftconfiguration, the covering/insulation 7 along the electrode/vibrationalelement 8 distal section 5 may be integral with the shaft 4covering/insulation or may comprise separate polymer coverings orinsulations secured to the electrode/vibrational element 8 and the shaft4.

As shown in FIGS. 28A to 28D, the pitch (A) between and the width (B) ofindividual windings determine the open space (e.g., opening or gap 10)for tissue to be urged into the lumen 6 of the probe and into contactwith the conductive windings by the external force of the suctionoriginating from a vacuum source 50. The pitch (A) is at least greaterthan or equal to 2 times the winding width (B) and is preferably greaterthan or equal to 3 times the winding width (B) to optimize theefficiency of engaging tissue to the electrode/vibrational element viathe suction. In two representative variations, the pitch of the probeswere 0.160″ and 0.120″ respectively, the electrode/vibrational elements8 winding width were 0.040″ for both devices, the widths of the openingsbetween each winding were 0.120″ and 0.080″ respectively, and theaverage length of the electrode/vibrational elements defined by theoverall aperture of the covering was 1.5″ (range 0.5″ to 2.5″).Configured thusly, the probes (when transmitting radiofrequency energyfrom a RF source 60) were able to consistently create transmural,continuous lesions in soft tissue spanning the length of theelectrode/vibrational element and having a depth greater than the widthof the opening. In addition, no hot spots were observed and the lesionsdemonstrated consistent tissue damage throughout the lengths. Theseresults were dramatically different to non-suction based approaches thatobserve hot spots in regions of intimate contact and shallow lesions inregions of lesser tissue contact.

FIGS. 29A and 29B show an alternative cut tube variation that, alongwith the covering/insulation and corresponding aperture(s) 20therethrough (as described above and shown in FIG. 28E) that expose theconductive windings of the cut tube comprising the electrode/vibrationalelement 8 of the probe. If the windings of the cut tube further extendaxially beyond the aperture 20 of the covering, then the cut tube mayalso comprise a portion or the entirety of the shaft 4 of the probe 2.This electrode/vibrational element 8 variation comprises multiplewindings that emanate from an axially extending backbone 36. Thewindings have at least one pitch (A) and at least one width (B), asshown in FIGS. 29A and 29B.

FIGS. 29C and 29D show an alternative variation where windings extendfrom a backbone and define openings between individual windings whereinthe windings define the conductive element of the electrode. Thebackbones 36 in these variations assist in maintaining the shape of thedeformed electrode/vibrational element 8 when pre-shaped to compliment,interface with or relatively match the soft tissue contours to betreated and provide stiffness to the probe during placement andpositioning of the electrode/vibrational element 8 against the softtissue surface. The backbone 36 alternatively provides increased columnstrength to improve the micro-motion caused by axial or radialdisplacement of the vibrational element 8 via the drive shaft coupled toa linear motor or rotary motor 70 when using mechanically-inducedultrasonic ablation.

Furthermore, is noted that alternative cutout tube geometries may beused for the electrode/vibrational element(s). Any geometry may sufficeso long as it defines windings (e.g., individual segments ofelectrode/vibrational element) extending from the probe axis between 0and 90 degrees that include openings 10 through which, in cooperationwith the aperture(s) 20 incorporated in the insulative covering 4,vacuum can be applied to force soft tissue between the openings 10 andinto direct engagement with the exposed windings.

FIGS. 30A and 30B show the distal section 5 of another integrated vacuumcoagulation probe 2 variation. This probe 2 incorporates at least oneelectrode/vibrational element 8 fabricated as a series of windings (in ahelix as shown, a backbone with associated windings/ribs, a mesh, orother configuration) from a cut tube or wound wire having at least onepitch or winding center-to-center separation (A) and at least onewinding width (B). The cut tube defines a vacuum lumen 6 for providing asuction path from a vacuum source 60 coupled to the handle. A polymercovering/insulation 7 is extruded, injection molded, or dipped over thecut tube to preserve the lumen 6 and provide at least one aperture 20that exposes the at least one opening 10 between individualelectrode/vibrational element 8 windings and the conductive surface ofsegments of individual electrode/vibrational element windings (as shownin FIG. 30B as a blackened section of the conductive windings). Theproximal region of the polymer covered cut tube defines the shaft 4. Asshown in FIG. 30B, the tissue contacting surface of thecovering/insulation along the opening 10 is offset from theelectrode/vibrational element 8 by a distance (D). The openings 10 alsocomprise at least one width (C) into which soft tissue is directly urgedinto engagement with the at least one electrode/vibrational element 8via suction.

The ratio between the offset (D) and the width (C) produces acoagulation response dependent on the application. For integrated,direct soft tissue coagulation, such as required during atrialfibrillation ablation or tendon shrinkage, C>2D to maximizes the contactbetween uneven or creased soft tissue surfaces and the exposed surfaceof the electrode/vibrational element winding(s). However, D ispreferably >0 for all variations (e.g., the covering/insulation extendsbeyond the at least one electrode/vibrational element) to enhance thesuction response of the vacuum coagulation probe.

By incorporating an offset D using the flexible polymercovering/insulator 7, the ability for the vacuum-integrated coagulationprobe 2 to contact soft tissue and produce a vacuum seal required toengage the soft tissue and bring it into engagement with the at leastone electrode/vibrational element 8 is dramatically improved. This isespecially important in applications where the soft tissue surface iscreased or uneven. The flexible covering/insulation 7 forms an extensionabout the at least one aperture 20 that fills the creases or unevenanomalies thereby preserving the suction force of the soft tissue to thevacuum-integrated coagulation probe 2 and ensuring the entire length ofsoft tissue engages the at least one electrode/vibrational element 8.

In addition, this offset D also has the ability to lift the tissue layerseparating it from underlying tissue layers. For example, during tendonshrinking applications of the shoulder, the tendon is engaged againstthe at least one electrode/vibrational element 8 via the suction and islifted from underlying nerves, or blood vessels thereby directly heatingthe tendon tissue while preserving the integrity and functionality ofthe underlying nerves and blood vessels. This feature is also importantduring atrial fibrillation treatment where underlying vessels such asthe circumflex artery, the right coronary artery, and the coronary sinusreside in the interatrial groove. When coagulating tissue completely tothe valve annulus to use the annulus as a barrier to electrical waveletpropagation, soft tissue along the interatrial groove is coagulated. Bylifting the atrial tissue along the interatrial groove and coolingunderlying tissue layers, the atrium is coagulated up to the interatrialgroove yet the underlying blood vessels, if any, are preserved.

For applications where the target tissue that the medical practitionerwants to heat resides between a definite soft tissue surface that needsto be preserved and the at least one electrode/vibrational element 8, agreater offset (D) is incorporated into the vacuum coagulation probe.Even so, C>D. This configuration addresses articular cartilage removalwhere jagged cartilage above the bony surface is heated and removed viathe vacuum without thermally damaging the underlying bony surface. Theintegrated electrode/vibrational element 8 and vacuum transmission ofthe vacuum coagulation probe variations of the invention enable directlyheating the target tissue by pulling the target tissue into engagementwith the edges of the electrode/vibrational element 8. The fluidperfusion mechanism enables cooling underlying tissue that is offsetfrom the electrode/vibrational element 8 to preserve that soft tissuelayer while evoking the desired effect on the contacted tissue layer.

As described above, the multilumen vacuum-integrated coagulation probeincorporates a distal tip opening 40 through which a suture, umbilicaltape, or flexible tube can be tied to apply tension against the distalend of the probe. In addition, a perfusion channel 100 integral to themultilumen covering 7 allows passage of fluid from a fluid source 55past the outlet 26 between the perfusion lumen 16 and the vacuum lumen 6to hydrate and cool soft tissue directly contacting theelectrode/vibrational element 8 and improve the transmission of energyto create deeper lesions required to ensure continuous, transmurallesions. As previously stated, a separate injector is not required toforce fluid through the perfusion lumen since the normally openperfusion passage is blocked only when a vacuum source 50 appliessuction to the vacuum lumen 6 and forces soft tissue into engagementwith the electrode/vibrational element 8 along the aperture(s) 20through the covering 7; in that situation, the suction force pulls thefluid from the fluid source 55, along the perfusion lumen 16, past theoutlet 26, and along the vacuum lumen 6.

As previously discussed, the electrode(s)/vibrational element(s) 8 atthe distal section 5 of the probe 2 will be routed to a signal generator60 via signal wires positioned within the shaft 4 (for transmission ofradiofrequency energy to at least one electrode), or to a linear motor70 or a rotary motor 80 via at least one drive shaft located within theshaft 4 (for mechanically-induced generation of ultrasonic energy).

These integrated, multilumen vacuum-integrated coagulation probevariations enable directly heating unwanted tissue superficial tohealthy tissue that needs to be preserved (e.g., articular cartilageremoval without damaging the underlying bone cells). The offset D ofelectrode 8 from the soft tissue surface and the passive injection ofcooling fluid provides a buffer from which only tissue urged intocontact via the suction is heated and removed without conducting heatdeeply into the underlying tissue. As such articular cartilage may beheated and removed while preserving the bony cells.

In this and other applications, the multilumen vacuum probe may perfusetherapeutic, pharmacologic solutions (e.g., gludaraldehyde, othercross-linking agents, hydrochloride, ethanol, heparin, rapamycin,paclitaxel, or other drug) from a fluid source 55 through the fluidperfusion lumen 16 and along tissue pulled into direct contact with theprobe 2 at aperture 20 via the vacuum. As such, toxic yet potentiallytherapeutic substances such as gludaraldehyde, etc. may be used toinvoke a tissue response while being quickly removed to avoid adverselyaffecting adjacent anatomy. As such the vacuum probe may cause tissueshrinkage by engaging tendons, or other soft tissue with a therapeuticcross-linking agent that is removed after exposing only a specificregion of tissue. Alternatively, drug solutions may be locallytransmitted to specific tissue regions to kill cells, alter cellularstructure, prevent a biological reaction, or other purpose. The isolatedinjection of therapeutic solutions may be augmented by the delivery ofradiofrequency or direct current energy (continuous or pulses) ormechanically-induced ultrasonic energy to cause electroporation or othertissue response to augment the impact of the therapeutic solutioninjection.

The variations described above may be treated so they are malleable andmay be deformed into a desired shape required to access the desiredcoagulation location and/or create the desired lesion length, and shape.An alternative approach to position the probe at the target anatomiclocation is to incorporate a steering mechanism in the vacuumcoagulation probe. The steering mechanism may be used to deflect theentire electrode/vibrational element relative to the shaft and/or aportion of the electrode/vibrational element. At least one pull-wire canbe secured to the electrode/vibrational element at theelectrode/vibrational element to shaft junction if theelectrode/vibrational element is to be deflected as a unit relative tothe shaft, or along the electrode/vibrational element up to the distalend of the probe if the electrode/vibrational element is to bedeflected. The opposite end of the pull-wire(s) may then be routed tothe handle and secured to an actuation knob (not shown) to manuallydeflect the vacuum coagulation probe into a curve. The curve shape,angle and radius is defined by the distance along or from theelectrode(s)/vibrational element(s) at which the pull-wire(s) is/aresecured and the stiffness relationship between the shaft and theelectrode(s)/vibrational element(s). A guide-coil or other radiallyrestraining component can be housed around the pull-wire(s) in the shaftto specify the stiffness of the shaft and further define the radius ofcurvature and angle of deflection of the distal region of the probe asthe pull-wires are actuated.

Existing atrial fibrillation coagulation or other soft tissuecoagulation treatment applications performed thoracoscopically,endoscopically, arthroscopically, laparoscopically, or with other lessinvasive approach tend to create incomplete curvilinear lesions becausethe desired lesion sites are inaccessible, contact to the tissue ispoor, and/or the temperature gradient from the contacted tissue surfaceto the opposite tissue surface is dramatic. These conditions limit thecreation of continuous, transmural, curvilinear, lesions. Suchlimitation is especially the case when blood is flowing along theopposite tissue surface producing a heat sink that cools that tissuesurface further affecting the temperature gradient and limiting thelesion depth. As such, the existing techniques can be inferior and havea higher rate of arrhythmia persistence than the vacuum coagulationprobe devices of the invention.

In addition, incomplete lesion creation during atrial fibrillationtreatment has been demonstrated to generate substrates for persistentatrial flutter and/or atrial tachycardia. For some other applications,the inability to create consistent and complete lesions allows cancerouscells, or other disease substrates to prevail. For applications such astendon shrinkage or articular cartilage removal, the inability to directcoagulation to a specific region of tissue without affecting underlyinglayers of tissue indiscriminately damages tissue structures (e.g.,nerves, blood vessels, bone cells, or other untargeted tissue) that needto be preserved. The same concern holds true for atrial fibrillationablation in which lesions extend to the interatrial groove where thecircumflex, right coronary artery, and coronary sinus reside near thevalve annulus and must be preserved. The variations of the inventionmitigate these risks by engaging isolated, target tissue regions andenabling direct coagulation of a specific region of tissue withoutdamaging unwanted tissue structures.

Rail Mechanisms for Manipulating Vacuum-Integrated Coagulation Probes

Remote access may be important for placing the vacuum-integratedcoagulation probe at the desired locations along the heart surface(epicardial or endocardial) to ensure therapeutic lesion sets arecreated. FIGS. 8A to 8C show an isometric view, a side view, and an endview of a rail mechanism 62 that directs the vacuum-integratedcoagulation probe variations along a defined path without the need forsteering mechanisms or stylets inserted through the perfusion channel,described above. As such, the flexibility of the vacuum-integratedcoagulation probe can be preserved and the rail mechanism 62 can addressall access requirements for the probe. As shown in FIGS. 8A to 8C,individual rail components 64 pivot relative to each other by sequentialball 66 and socket joints that permit rotation in 3-dimensions ofindividual rail components 64 to each other. The ball 66 and socketjoints incorporate a central lumen 82 through which a flexible rod canreside. A nut incorporated at the handle end (not shown) of the railmechanism 62 can be coupled to the flexible rod and tightened to furtherengage the individual ball features 66 of the rail components 64 againstthe mating sockets to lock the rail mechanism in the shape the railmechanism was manipulated at the time the nut was used to tighten therail components along the flexible rod. Two pull-wires are insertedalong the lateral channels 68 of individual rail components to helpmanipulate (e.g., steer) the rail components by actuating the twopull-wires relative to each other and relative to the flexible rod tomaneuver the rail mechanism into various 3-dimensional shapes. Once thepull-wires are used to position the rail mechanism 62, the railcomponents 64 are tightened along the flexible rod to maintain thedesired shape. After positioning and locking the rail mechanism 62, thevacuum-integrated coagulation probe 2 can be advanced along the raillumen 84 of the rail mechanism 62, as shown in FIGS. 9A to 9D.

As shown in FIG. 9D, the perfusion channel/tube 100 outer profile alongthe distal section 5 of the probe matches the inner shape of the railmechanism and locks within the rail components' 64 lumens 84 so the railmechanism 62 maintains the position of the probe 2 distal section 5while allowing the probe to be advanced along the rail mechanism. Oncethe vacuum-integrated coagulation probe 2 is advanced into positionalong the rail mechanism 62, the rail mechanism can be furthermanipulated (e.g., steered) and locked into a new position therebyrepositioning the distal end of the vacuum-integrated coagulation probe.Further, it should be noted that the lumen 84 of the rail mechanism 62can be configured to match another cross-sectional segment of thevacuum-integrated coagulation probe 2 including the entire cross-sectionto lock the probe to the rail mechanism while preserving the ability toadvance and retract the probe relative to the rail mechanism.

FIG. 10 shows an alternative rail mechanism 62 that comprises a unitarytubular structure that incorporates an opening along one side of thetubular structure and defines a lumen 84. The opening and lumengeometries ensure the perfusion channel/tube or the entire distalsection 5 cross-section of the vacuum-integrated coagulation probe 2 tolock the probe 2 within the rail mechanism 62 but preserves the abilityto readily advance and retract the vacuum-integrated coagulation probealong the rail mechanism.

The rail mechanisms described above can support dissecting/tunnelingtools (described below) and/or endoscopic optics/cameras to facilitatepositioning the rail mechanism at the desired location around the heartor other anatomic structure. As described below, a dissecting/tunnelingmechanism can pass along the lumen of the rail mechanism to facilitateplacement of the rail mechanism as fat tissue is dissected and thedissecting/tunneling tool is positioned at the desired location. Therail mechanism can also house an endoscopic camera (through the lumen 84of the rail mechanism 62, the ball and socket lumen 82, or another lumen68 incorporated in the individual rail components 64) to directlyvisualize placement of the rail mechanism, dissecting/tunneling, orcoagulation processes. In addition, the flexible rod and/or pull-wirescan comprise fiberoptics to incorporate a light source to assistvisualization of tissue approximate the distal end of the railmechanism.

Atrial Fibrillation Treatment Using Vacuum-Integrated Coagulation Probes

An approach for treating atrial fibrillation with the vacuum-integratedcoagulation probe of the invention is described. In one method, theprobe is inserted into the thoracic cavity through incisions, trocars,or other access aperture placed in intercostal spaces, a thoracotomy, athoracostomy, a median sternotomy, a mini-sternotomy, a subxyphoidaccess port, a lateral subthoracic access site, or other less invasivesurgical procedure. As such, the distal section and shaft of the probehave low profiles to facilitate advancing through small cavitiesassociated with limited access applications.

FIGS. 11A, 11B, and 11D show an isometric view, a side view, and a topview of a trocar assembly 104 variation that incorporates an ellipticalor oval cross-section and a locking feature that engages the interiorsurface of the chest once inserted into the thoracic cavity. FIG. 11Cshows the dilator component 112 of the trocar assembly that ispositioned into the trocar sheath 106 during insertion through the chestwall. The dilator component 112 incorporates notches 117 through whichthe movable locking legs 114 of the trocar sheath (FIG. 11E) can rotate.During insertion, as shown in FIGS. 11A, 11B, and 11D, the dilatorcomponent 112 (FIG. 11C) resides through the lumen 119 of the trocarsheath 106 (FIG. 11E) and the locking legs 114 of the trocar are closedto provide a smooth transition from the pointed tip 116 of the dilatorcomponent 112, along the tapered distal section 115 of the trocar, andalong the outer surface of the trocar sheath 106.

Once the trocar assembly 104 has been inserted through the skin and pastthe chest wall such that the distal end of the trocar sheath residesinside the thoracic cavity, the locking legs 114 are rotated relative tothe trocar sheath 106 releasing the dilator component 112 from thetrocar sheath 106 and preventing retraction of the trocar sheath 106from the chest. FIGS. 12A to 12C show an isometric view, a side view,and a top view of the deployed trocar sheath 106 with the locking legsrotated into a locking position such that they engage the interiorsurface of the chest wall. As shown in FIGS. 11E and 12C, thecross-section of the trocar sheath 106 is elliptical or oval having alumen 119 length (L) at least three times the lumen width (W). The lumen119 width (W) ranges from 2 mm to 12 mm and the lumen length (L) rangesfrom 6 mm to 60 mm. Alternatively, the cross-section may be rectangularor substantially rectangular with radiused corners as long as the lumen119 length (L) is at least three times the lumen 119 width (W). Theelongated cross-sectional geometry of the trocar sheath 106 supports theopening through the chest wall to allow passage of the vacuumcoagulation probe or other instruments and facilitates manipulation ofthe device since rotation along the length (L) of the trocar sheath 106lumen 119 increases the range of movement of the device within thetrocar sheath 106 without applying excess pressure on the chest wall.The trocar sheath will be fabricated from a polymer (e.g.,polycarbonate, PTFE, polyimide, polyurethane, other polymer, or braidedtubing having the desires cross-section and geometry) that supports theopening to the chest wall and will not deform easily while the device ismanipulated within the trocar sheath lumen.

Once inserted into the thoracic cavity (e.g., through the elongatedcross-section trocar), the probe may be deflected or deformed into thedesired lesion pattern, comprising slight curves passing along thesurface of the heart, for example between the left pulmonary vein andright pulmonary vein. As described above, the vacuum-integratedcoagulation probe may incorporate steering or preshaped stylets tomanipulate the position within the thoracic cavity. Alternatively, arail mechanism, as shown in FIGS. 8A to 8C, 9A to 9D, and 10 anddescribed above, may be positioned at the target lesion location andused to lock and advance the probe into position along the railmechanism. Once placed, the vacuum source is actuated to apply a suctionforce through the vacuum opening(s) of the electrode(s)/vibrationelement(s) and through the covering aperture to urge the epicardium ofthe left atrium 36 into intimate contact with theelectrode(s)/vibrational element 8. It should be noted that thevacuum-integrated coagulation probe can instead be placed against theendocardium of the atria during cardiopulmonary bypass procedures wherethe atria are open for valve (mitral, tricuspid, and/oratrioventricular) repair or replacement procedures or beating heartprocedures where an introducer into the atrium is obtained through anatrial appendage, the atrial free wall, the ventricle, a pulmonary vein,a vena cava, or other conduit that may be closed upon completion of thecoagulation procedure.

Given the flexibility for application of the subject devices, anypattern of curvilinear, transmural lesions may be created along theepicardial surface or the endocardial surface with the vacuumcoagulation probe variations of the invention. One left atrial lesionpattern involves creating a “C” that passes from the mitral valveannulus adjacent the left atrial appendage (where the great vein and thecircumflex do not parallel the atrioventricular annulus but have curvedtowards the apex of the left ventricle) above the superior pulmonaryvein and back towards the mitral valve annulus adjacent the rightpulmonary veins; or below the inferior pulmonary veins and towards theanterior mitral valve annulus. Another left atrial lesion patterninvolves creating a “V” where the intersection resides at the mitralvalve annulus adjacent to the left atrial appendage and each segmentpasses on opposite sides of the pulmonary veins and ends adjacent to theinteratrial septum. A stretched “B” with each curved segment extendingaround either the left pulmonary veins or the right pulmonary veins andthe central links separated by a distance wherein the top line of the“B” connects to the mitral valve annulus adjacent the left atrialappendage. A stretched “S”, reverse “S”, or figure eight with theinitiating point occurring at the mitral valve annulus adjacent to theleft atrial appendage and curving from that base point to encompass theleft and right pulmonary veins as pairs within the curved segments. Inaddition to the various left atrial lesion patterns above, right atriallesions may be created along the cristae terminalis, from the inferiorvena cava to the superior vena cava, from the cristae terminalis to thetricuspic annulus, from the superior vena cava to the tricuspid annulus,or other geometry capable of preventing atrial flutter along the rightatrium. Alternative potential lesion patterns capable of treating atrialfibrillation, which the vacuum coagulation probe may replicate, aredescribed in U.S. Pat. No. 6,071,279 entitled “Branched structures forsupporting multiple electrode elements” and incorporated herein byreference.

Advantageously, the entire length of the exposedelectrode(s)/vibrational element is used to apply suction through the atleast one opening 10 to apply a vacuum force against the epicardium (orendocardium) and urge the tissue into engagement with theelectrode(s)/vibrational element. For electrical heating of soft tissue,radiofrequency (or D.C.) energy is transmitted to tissue heatingelectrode(s) in unipolar or bipolar mode such that the current densityis transmitted into tissue adjacent the at least one electrode and ohmicheating causes the tissue adjacent the at least one electrode to heatand conduct the heat further into depths of tissue. Alternatively, theelectrode(s) may be fabricated from a resistive element (e.g., tantalum,tungsten, Nichrome, etc.) in which radiofrequency (or D.C.) energyapplied along the resistive element, between wire connections atopposite ends of the resistive element, heats the element and theintimate tissue to electrode(s) contact enables thermal conduction ofthe heat from the electrode into the target soft tissue.

Alternatively for mechanically-induced ultrasonic heating, a drive shaftis secured to the vibrational element(s) and a linear or rotary motor isused to cycle the displacement (linear or angular) of the vibrationalelement(s) at a high frequency and small displacement (linear orangular). As such, a mechanically-induced ultrasonic wave is transmittedfrom the vibrational element(s) into soft tissue directly contacting thevibrational element(s) or coupled to the vibrational element(s) via afluid path. The mechanically-induced ultrasonic wave causes cavitationwhich imparts heating of the soft tissue above a threshold where thesoft tissue becomes electrically non-viable but structurally strong.

The transmission of radiofrequency energy in unipolar or bipolar mode,or of mechanically-induced ultrasonic energy causes the soft tissue toheat which conducts further into adjacent soft tissue; alternatively theheating of a resistive element causes the resistive electrode(s) to heatwhich is then conducted into adjacent, contacted soft tissue. As cardiaccells (and any muscle tissue) are heated above 50° C., irreversibleconduction block occurs and the cells become non-viable (Nath, et al.Cellular electrophysiologic effects of hyperthermia, on isolated guineapig papillary muscle: implications for catheter ablation. Circulation.1993; 88:1826-1831). As such, a consistent, continuous length of atrialtissue extending from the epicardial surface to the endocardial surfacemust be heated above 50° C. to treat atrial fibrillation.

Additional Applications Utilizing the Vacuum-Integrated CoagulationProbes

For other applications involving coagulation of soft tissue to shrinkcollagen rich tissues or prevent shrinking of collagen tissues, heatingof the soft tissue must be controlled, which the vacuum coagulationprobe variations of the invention enable. Published studies evaluatingthe response of vessels (arteries and veins) to heat have focused on theability to permanently occlude vessels. Veins have been shown to shrinkto a fraction of their baseline diameter, up to and including completeocclusion, at temperatures greater than 70° C. for 16 seconds; thecontraction of arteries was significantly less than that of veins butarteries still contracted to approximately one half of their baselinediameter when exposed to 90° C. for 16 seconds (Gorisch et al.Heat-induced contraction of blood vessels. Lasers in Surgery andMedicine. 2:1-13, 1982; Cragg et al. Endovascular diathermic vesselocclusion. Radiology. 144:303-308, 1982). Gorisch et al explained theobserved vessel shrinkage response “as a radial compression of thevessel lumen due to a thermal shrinkage of circumferentially arrangedcollagen fiber bundles”. These collagen fibrils were observed todenature, thus shrink, in response to heat causing the collagen fibrilsto lose the cross-striation patterns and swell into an amorphous mass.

Variations of the invention prevent or limit the heat-inducedcontraction of such structures as the pulmonary veins by applying avacuum force capable of maintaining the position (e.g., diameter) of thevessel while heating the soft tissue. As such, the vessel is stented orsupported from the external surface as the tissue is heated above therequired 50° C. threshold without concern that the vessel mayaccidentally become stenosed due to the heat-induced contraction.

Alternatively, the vacuum coagulation probe variations directheat-induced contraction of such structures as tendons, ligaments, skinor other anatomy in which the therapy is designed to heat therebydenature the collagen and shrink the tissue until the desired shape oreffect is achieved. In addition, the vacuum coagulation probe canreposition the soft tissue while heat is applied to the soft tissue todirect the shrinking and cause the collagen fibrils to reorganizereforming the soft tissue into a desired shape.

The integrated vacuum coagulation probe variations above can also beutilized in shrinking tendons, ligaments, or otherwise modifying suchcollagen-based tissue structures either by locally heating the targettissue layer as described above or transporting cross-linking agents(e.g., gludaraldehyde) or other pharmacological substances specificallyto the region of soft tissue engaged against the opening(s) 10 of theprobe. As such these typically toxic materials are also removed afterinvoking their desired tissue response. Cross-linking agents have beendemonstrated to cause collagen-induced shrinking of tissue structuresand increase the strength of such structures; therefore, they are highlysuited, despite their toxicity, to strengthening and shrinking damagedtendons. As such these integrated vacuum coagulation probe variationsenable treated the tissue with such agents without concern for theirtoxicity since they are immediately removed by the vacuum.

The integrated vacuum coagulation probe variations of the invention alsoenables treating a tissue surface without damaging underlying tissuestructures (e.g., nerves or vascular tissue) by slightly lifting thetarget tissue surface away from the underlying layers via the vacuumwhile coagulating the target tissue layer. As such, the underlyingtissue is preserved.

Theranostic Probe Variations

The term “theranostic” refers to the ability to determine the outcomesof a therapeutic procedure by using diagnostic devices and methods. Inthe variations described below, theranostic devices refer tointraoperative diagnostic devices that determine whether a therapeuticminimally invasive surgical procedure has been effective ataccomplishing its task.

The vacuum-integrated coagulation probes described above and shown inFIGS. 1A to 1C, 2A to 2E, 3, 4A to 4C, 5A and 5B, 6A to 6F, and 7A to 7Imay be used as theranostic probes. In adapting those vacuum-integratedcoagulation probes to theranostic devices, a stimulator/pacemaker isconnected to the electrical connections 14 at the handle of thetheranostic probe. The stimulator delivers pacing pulses to theelectrode(s) 8 that is/are held into engagement with the soft tissuesurface (e.g., pulmonary vein, atrial wall, or ventricular wall) via thevacuum-integrated features to stimulate electrical propagationthroughout the atria or ventricles and determine if the therapeuticprocedure achieved the desired results.

These adapted theranostic probe variations do not require perfusiontubes, as shown in some of the vacuum-integrated coagulation devicevariations, but would require at least one electrode that definesopenings and a covering that incorporates an aperture to expose theopenings and the electrode windings. The vacuum source is coupled to thevacuum lumen and the openings between the electrode windings such thatupon activation of the vacuum source, soft tissue is pulled into directengagement with the electrode(s) 8 whereby manual pressure is notrequired to maintain the device into contact with the soft tissuesurface. Once the electrode is urged into engagement with soft tissue,pacing pulses are transmitted into soft tissue to stimulate the softtissue and determine conduction characteristics and/or determine whetheran arrhythmia substrate is inducible. By stimulating one region oftissue (e.g., near or on the pulmonary veins) conduction to the atrialwall can be evaluated to determined whether adequate conduction block orpathways have been created. To induce an arrhythmia, various programmedstimulation protocols can be utilized to determine the ability toinitiate an arrhythmia. Alternatively, rapid pacing involvingtransmitting pacing pulses at a rate faster than sinus rhythm may beutilized to determine whether the arrhythmia can be initiated. Thosesame electrodes may also be used to transmit electrical signals producedby the soft tissue to a mapping system or signal acquiring instrumentcapable of conditioning, displaying, and/or recording the electrogramsignals.

FIGS. 13A to 13C and 14 show two alternative theranostic probe 120variations. In each of these variations, the electrode comprises twoconductive segments 128 or 138 separated and bonded with an insulativelayer to provide transmission of pacing stimuli in bipolar fashionbetween the discrete, separate conductive segments without the need fora large reference ground pad. The conductive segments 128 or 138 defineat least one opening 10 through which the vacuum lumen is coupled. Acovering 15 defines an aperture 20 that exposes the conductive segments128 or 138 of the electrode and the opening(s) 10. The distal segment isconnected to a shaft 4 that is routed to a handle 102. A vacuum controlknob 54 determines when vacuum is being applied by the vacuum source 50.The electrodes conductive segments 128 or 138 are routed to a stimulator90 with signal wires contained within the shaft 4 and attached to aconnector in the handle to which the stimulator 90 can be connected.

FIGS. 15A and 15B show an isometric view and an end view of theelectrode assembly for the theranostic probe variation in FIGS. 13A to13C. In this electrode assembly, two conductive segments 128 that eachextend less than 180 degrees are attached together with insulativeadhesives or mechanical insulative structures 126 such that they faceeach other to define an opening 10 but are electrically insulated fromeach other. Each conductive segment 128 is connected to a separate wire,each of which is routed to a connector, which is coupled to thestimulator.

FIGS. 16A and 16B show the electrode subassembly for the theranosticprobe variation in FIG. 14. This electrode subassembly incorporates tworing conductive segments 138 having different diameters such that onefits within the other and is separated by a electrically insulativeadhesive or structure 126, again to ensure mechanical stability thatdefines a central opening 10 and electrical insulation of the discreteconductive segments. The electrode subassemblies are housed in a flaredcovering 15 that defines an aperture 20, as shown in FIGS. 13A to 13Cand 14. Each electrode subassembly includes a central opening 10 throughwhich the vacuum lumen is coupled in order to pull soft tissue intodirect engagement with the electrode while transmitting pacing stimuli.An elongated, flexible shaft connects the electrode subassembly to thehandle and preserves the vacuum lumen to ensure the electrodesubassembly engages soft tissue without manually pushing the probeagainst the tissue surface, which could cause damage to the tissuesurface or perforation of the tissue structure. The electrodes areconnected to a stimulator/pacemaker 90 via an electrical connectorhoused in the handle 102 of the device.

FIGS. 17A to 17E show an isometric view, a front view, a side view, abottom view, and a sectional view of an alternative theranostic probe120 variation. This theranostic probe variation incorporates discretering electrodes 18 that are separate from each other to define at leastone opening 10 and are individually insulated 38 to ensure signalsreceived by each electrode 18 are individually transmitted throughdedicated signal wires, contained within the shaft 4, to anelectrophysiology recorder, electrogram mapping system, or other devicecapable of acquiring, conditioning, displaying, and/or recordingbiological signals.

Similarly, pacing stimuli may be transmitted from apacemaker/stimulator, along individual signal wires, through individualelectrode rings 18, and into contacting soft tissue in monopolar mode(between a discrete ring electrode and a large surface area ground pad)or bipolar mode (between individual electrodes). An insulative covering7 is located along the distal section 5 of the probe to define at leastone aperture 20 the exposes the electrodes 18 and the opening(s) 10between discrete electrodes. Since this configuration orients the distalsection 5 perpendicular to the shaft 4 axis (as opposed to previousconfigurations that were oriented axially), the covering 7 in the distalsection 5 defines a conduit 28 that couples the vacuum lumen 6 to theopening(s) 10 and the aperture 20. The covering also contains externalribs 30 that aid in maintaining the aperture 20 side-separation as thedistal section 5 is manipulated into a curved shape.

Dissecting/Tunneling Variations

FIGS. 18A to 18C, 19A to 19H, 20A to 20D, and 21A to 21C showdissecting/tunneling tool 124 variations of the invention that aredesigned to remove or separate adipose tissue (e.g., fat) and/orinterconnective tissue from the heart. The purpose of such action is toexpose muscle layers and permit maneuvering the vacuum-integratedcoagulation probe into engagement with heart tissue at any location,whether or not previously covered by fat or interconnective tissue.

As shown in FIGS. 18A to 18C, an outer covering comprising a multiplelumen tubing defines a vacuum lumen 6 housing a moveable vibrationalelement 108 that contains windings oriented substantially perpendicular,or at a 45 to 90 degree angle from the axis of the device. The coveringmaintains adequate rigidity to stabilize the moving vibrational element108 but is flexible to follow tortuous pathways around the heart andposition the aperture 120 through the covering that exposes the windingsof and openings 110 between individual windings of the vibrationalelement 108 against the heart epicardial wall. The vibrationalelement(s) 108 are couple to a drive shaft that passes along the vacuumlumen 6 and is coupled to a linear motor 70 via a mechanical coupler.The vacuum lumen 6 is coupled to a vacuum source 50. A fluid perfusionlumen 16 defined by the perfusion channel or tube 100 incorporated inthe dissecting/tunneling tool is coupled to the vacuum lumen 6 at anoutlet 26 to enable passing fluid from a fluid source 55 and along softtissue contacting the vibrational element(s). This fluid source 55 cancomprise a detergent or other pharmacologic agent that facilitatesemulsification of adipose (e.g., fat) tissue.

In use, the dissecting/tunneling tool is positioned against fat tissueand the linear motor is activated causing the vibrational element(s) tomove axially at a high cycle rate (e.g., 5 kHz to 1 MHz and preferably15 kHz to 30 kHz) and small displacement (e.g., <5 mm and preferably <1mm). As such, the fat is locally heated and separated from heart muscletissue to facilitate removal. The vacuum source 50 is used to constantlypull the separated fat tissue through the vacuum lumen 6 and into areservoir that collects the fat remnants. This dissecting/tunneling tool124 is able to adequately remove or separate fat tissue to permitcontacting the vacuum-integrated coagulation probeelectrode(s)/vibrational element 108 into direct engagement with muscle.

FIGS. 19A to 19G show an isometric view, a side view, a bottom view, aside-sectional view, and three cross-sectional views of an alternativedissecting/tunneling tool 124 that utilizes a rotational vibrationelement 118 (shown in FIG. 19H) that is coupled to a rotary motor 80 viaa drive shaft. The rotary motor 80 produces a high frequency (e.g., 5kHz to 1 MHz and preferably 15 kHz to 30 kHz) angular displacement(e.g., <90 degrees and preferably <30 degrees) of the rotationalvibrational element to separate and remove fat deposits from around theheart. As discussed above, the vibrational element 118 resides withinthe vacuum lumen 6 defined by the covering such that it engages softtissue along the aperture 122 created in the side wall of the covering.

Openings 110 between individual windings allow vacuum force to beapplied directly to the soft tissue surface and pull soft tissue intoengagement with the vibrational element 118. Also, fat tissue that isseparated is pulled into the vacuum lumen 6 and is transported into areservoir coupled to the vacuum source 50. Optional perfusion lumen 16defined by a perfusion channel or tube 100 allows fluid from a fluidsource 55 to pass through an outlet 26 between the perfusion lumen 16and the vacuum lumen 6, and along soft tissue contacting thedissecting/tunneling tool 124 at the aperture 122 and along thevibrational element 118.

FIGS. 20A to 20D show an isometric view, a side view, a top view, and anend view of another dissecting/tunneling tool 124 variation capable ofseparating fat tissue. In this variation, two laterally expandable legs72 oriented along each side of the central drive shaft 76 are connectedto a distal segment that incorporates a tapered distal tip 74 to passbetween layers of tissue. The tapered distal tip 74 is also connected tothe drive shaft 76, which further extends through the shaft 78 of thedevice to the handle where it is connected to an actuation knob. As thedrive shaft 76 is retracted, the legs 72 bow outward laterally and applydissecting pressure on tissue residing around the legs. The drive shaft76 may further be coupled to a linear motor to further impart highfrequency axial displacement of the tapered distal tip thus the laterallegs to augment the mechanical expansion of the fat tissue layers, whichcauses separation, with ultrasonic heating and emulsification of fatcontacting the tapered distal tip and/or the laterally bowing legs.

The dissecting/tunneling tool 124 may incorporate a guide mechanism 86that mates with the central lumen 84 of the rail mechanism 62 asdiscussed above. As such, the dissecting/tunneling tool 124 may be usedto position the rail mechanism 62 into the desired location along theheart such that once the desired dissection and/or tunneling has beenachieved, the dissecting/tunneling tool 124 may be removed so thevacuum-integrated coagulation probe may be advanced along the railmechanism 62 and into position against the target soft tissue segment.

FIGS. 21A to 21C show side-sectional views of the variation of thedissecting/tunneling tool 124 in FIGS. 20A to 20D. FIG. 21A shows thetapered distal tip 74 fully extended to compress the legs 72 against thedrive shaft 76. FIG. 21B shows tension applied to one of the laterallegs 72 that deflects the tapered distal tip 74 thus steers the distalsection of the tool. FIG. 21C shows the drive shaft 76 retracting thetapered distal tip 74 thus expanding the laterally bowing legs 72. Thedrive shaft that is attached to the tapered distal tip is routed throughthe central lumen of the shaft 98 and is connected to the handle 94. Asthe handle 94 is actuated (e.g., squeezed) the drive shaft 76 isretracted causing the tapered distal tip to be retracted and the legs tobe bowing laterally outward. As shown in FIGS. 21A to 21C, the laterallegs of this dissecting tool variation are connected to a pivotingmember 96 that is further attached to an axially movable knob 92 by apull-wire. As the pull-wire is advanced, shown in FIG. 21B, the pivotingmember rotates and applies tension to the upper lateral leg therebydeflecting the tapered distal tip. If the pull-wire is retracted, notshown, the tapered distal tip would be deflected in the oppositedirection. Alternatively, one or both lateral legs can be routed throughthe central lumen of the shaft and connected to individual knobs at thehandle to be independently actuated.

FIG. 22 shows an alternative dissecting/tunneling instrument 124 thatcomprises blunt jaws 140 that pivot relative to each other. The jaws 140are connected to a drive shaft 76 via links 142 that direct the rotationof the jaws relative to the pivot point. The drive shaft 76 is containedwithin the shaft 98 that contains a central lumen. The drive shaft 76connects to the handle arms 94 through proximal links 144 that allowaxial movement of the drive shaft as the handle arms are actuated. Thisdissecting clamp incorporates a mechanical coupler that connects thedrive shaft 76 thus the jaws 140 of the dissecting clamp to a linearmotor 70 that produces a high frequency displacement causing thedissecting clamp jaws 140 to vibrate and induce an ultrasonic wavecapable of separating, emulsifying, or otherwise modifying fat tissue toseparate it from muscle tissue. An endoscopic visualization tool may bemounted on the dissecting clamp or inserted through a central lumen inthe dissecting clamp to provide direct visualization of the distal endof the dissecting clamp and tissue that is modified with themechanically-induced ultrasonic dissecting clamp.

Mechanically Vibrating Ultrasonic Ablation Catheters

FIGS. 23A to 23C and FIGS. 24A to 24C show isometric views, side viewsand top views of two mechanically vibrating ultrasonic ablation cathetervariations 150 that access the soft tissue via the vasculature. In thesecatheter variations, no electrical wire connections are required totransmit energy capable of heating soft tissue to render the tissueelectrically non-viable or evoke another heat-induced tissue response.

The catheter variation in FIGS. 23A to 23C comprises a unitary elongatemember 152 that passes through a sheath 154 and curves into a reversespiral emanating from the proximal section 160 of the elongate member.The proximal end of the elongate member is connected to a mechanicalvibration mechanism (e.g., linear motor 70 or rotary motor 80), via amechanical coupler, that moves the distal, curved, expanded section 156of the elongate member axially or radially at a high frequency (e.g., 5kHz to 1 MHz and preferably 15 kHz to 30 kHz) and small displacement (<1mm). The sheath 154 isolates the vibrating elongate member 152, thus themechanically-induced ultrasonic energy, from surrounding vascular tissuethrough which the catheter 150 is advanced to access the endocardialsoft tissue surface. Because the unitary elongate member 152 utilizesmechanical motion to vibrate and emit ultrasonic energy, the elongatemember 152 does not require separate electrodes or transducers. Neitherdoes it require spot welds, solder joints, adhesive bonds, or otherattachment processes that stiffen the device or inhibit the ability tobend, expand, or compress the device. Still, a variation of a deviceaccording to the invention may include such features.

FIGS. 24A to 24C show another mechanically vibrating ultrasonic ablationcatheter 150 variation that incorporates two circular or ellipticalloops intersecting into an “X” as shown in FIG. 22B and extending toproximal segments 160 that pass through a sheath 154. This variation ofthe invention may comprise a unitary member 152 fabricated from a tubelaser cut, chemically etched, or otherwise cut into the “X” distalsection 158 with proximally extending segments 160. Alternatively, thedistal “X” section 158 may be fabricated as one or two components andsecured to the proximal segments via attachment processes previouslydescribed. Also, the loops of the distal “X” section 158 may compriseseparate loops interlaced and bonded at the intersections to form thedistal section. For these configurations, the elongate member 152 thatdefines the mechanically vibrating ultrasonic ablation catheter 150 doesnot require separate electrodes, transducers, or the requisite bondingprocesses required to attach electrodes and transducers.

As shown in FIGS. 25A and 25B, the mechanically vibrating ultrasonicablation catheter 150 variation in FIGS. 23A to 23C is advanced intoengagement with a single pulmonary vein 164 and expanded into contactwith the orifice 162 of the pulmonary vein to contact atrial tissue atthe pulmonary vein 164 such that as the linear motor 70 or rotary motor80 is actuated, micro-motion of the distal, contacting segment 156 ofthe catheter at a high cycle rate causes cavitation of adjacent softtissue thereby heating the atrial tissue at the orifice 162 to thepulmonary vein 164.

FIGS. 26A and 26B shows the mechanically vibrating ultrasonic catheter150 variation in FIGS. 24A to 24C inserted at the orifice 162 to thepulmonary vein 164 and expanded into contact with atrial tissue and thepulmonary vein. As described above, actuation of the linear motor 70 orrotary motor 80 causes rapid movement of the distal section 158 causingvibrations that emit an ultrasonic wave capable of causing cavitationand heating of adjacent soft tissue. As the soft tissue heats above 50degrees Celsius, irreversible conduction block occurs rendering thetissue, adjacent the pulmonary vein and in contact with the mechanicallyvibrating catheter 150 distal section 158, electrically non-viable andinhibiting cells inside the pulmonary vein 164 from stimulating atrialtissue outside the pulmonary vein 166.

In operation, a transeptal sheath 154 is inserted via conventionaltechniques through the venous system, through the right atrium, past theinteratrial septum at the fossa ovalis, and into the left atrium 166.Once the sheath intravascularly accesses the left atrium, 166 a separatesteerable catheter is used to place the distal end of the sheathadjacent or into a pulmonary vein 164. The unitary elongate member 152that defines the mechanically vibrating ultrasonic ablation catheter 150is compressed into a small diameter to fit inside the sheath 154. Theelongate member 152 is advanced through the sheath 154 and into thepulmonary vein 164 where it extends beyond the distal end of the sheath154 and expands into contact with the pulmonary vein 164 at the orifice162. Once positioned, the elongate member 152 can be advanced orretracted to encourage engagement with the orifice 162 to the pulmonaryvein 164. The variation in FIGS. 23A to 23C fits against the orifice 162to the pulmonary vein 164 to circumferentially contact the orifice 162of the pulmonary vein 164. Alternatively, the distal section 156 can beinserted completely into the pulmonary vein 164.

The variation of the invention in FIGS. 24A to 24C creates a distalsection 158 of intersecting loops that has a variable expansion profilesuch that the proximal end of the distal section 158 expands more thanthe distal end of the distal section 158 to lock the elongate member 152into the pulmonary vein 164 and match the contours of the distal sectionto the orifice 162 of the pulmonary vein 164. The intersecting “X” loopsencourage expansion of the distal section 158 into intimate engagementwith the orifice 162 of the pulmonary vein 164 (or within the pulmonaryvein itself), and ensure that any cross-section of the pulmonary vein164 is not contacted by the mechanically induced ablation member alongmore than 90 degrees of the inner circumference of the pulmonary vein164. As such, the risk of pulmonary vein stenosis due to heat-inducedcontraction of collagen within the pulmonary vein 164 is mitigated andthe degree of contraction is dramatically reduced versus ablation energytransmission configurations that ablate more than 180 degrees around thepulmonary vein 164 at any cross-sectional plane through the pulmonaryvein 164. Once the elongate member 152 is expanded into contact with thepulmonary vein 164 and/or orifice 162, the linear motor 70 or rotarymotor 80 is activated thereby causing high frequency, small displacement(e.g., <1 mm) of the distal section 158 of the elongate member 152 whichcauses vibration of the contacted soft tissue and surrounding fluid.This vibration produces an ultrasonic signal capable of heating softtissue along the orifice 162 of the pulmonary vein 164 or within thepulmonary vein.

As noted herein, variations of the invention may have an elimination ofseparate electrodes, transducers, electrical wire solder joints or spotwelds, and adhesive bonds. In such variations this benefit allows, amongothers, a decrease in the diameter of the sheath through which theelongate member can be inserted, an improvement in the physicalintegrity of the ablation catheter, and an increased ability inmanipulating the elongate member 152 through the vasculature and intoengagement with the orifice 162 to the pulmonary vein 164.

Methods

The methods herein may be performed using the subject devices or byother means. The methods may all comprise the act of providing asuitable device. Such provision may be performed by the end user. Inother words, the “providing” (e.g., a delivery system) merely requiresthe end user obtain, access, approach, position, set-up, activate,power-up or otherwise act to provide the requisite device in the subjectmethod. Methods recited herein may be carried out in any order of therecited events which is logically possible, as well as in the recitedorder of events. In addition, variations of the invention may be used incoagulating other soft tissues such as breast tissue, the liver, theprostate, gastrointestinal tissue, skin, or other soft tissue for thecoagulation of cancerous cells; or other collagen based soft tissue forthe heat induced shrinking or contraction.

Variations

Various exemplary variations of the invention are described below.Reference is made to these examples in a non-limiting sense. They areprovided to illustrate more broadly applicable aspects of the presentinvention. Various changes may be made to the invention described andequivalents may be substituted without departing from the true spiritand scope of the invention. In addition, many modifications may be madeto adapt a particular situation, material, composition of matter,process, process act(s) or step(s) to the objective(s), spirit or scopeof the present invention. All such modifications are intended to bewithin the scope of the claims made herein. Exemplary aspects of theinvention, together with details regarding material selection andmanufacture have been set forth above. As for other details of thepresent invention, these may be appreciated in connection with theabove-referenced patents and publications as well as generally know orappreciated by those with skill in the art.

The same may hold true with respect to method-based aspects of theinvention in terms of additional acts as commonly or logically employed.In addition, though the invention has been described in reference toseveral examples, optionally incorporating various features, theinvention is not to be limited to that which is described or indicatedas contemplated with respect to each variation of the invention. Variouschanges may be made to the invention described and equivalents (whetherrecited herein or not included for the sake of some brevity) may besubstituted without departing from the true spirit and scope of theinvention. In addition, where a range of values is provided, it isunderstood that every intervening value, between the upper and lowerlimit of that range and any other stated or intervening value in thatstated range is encompassed within the invention.

Also, it is contemplated that any optional feature of the inventivevariations described may be set forth and claimed independently, or incombination with any one or more of the features described herein.Reference to a singular item, includes the possibility that there areplural of the same items present. More specifically, as used herein andin the appended claims, the singular forms “a,” “an,” “said,” and “the”include plural referents unless the specifically stated otherwise. Inother words, use of these articles allow for “at least one” of thesubject item in the description above as well as the claims below. It isfurther noted that the claims may be drafted to exclude any optionalelement. As such, this statement is intended to serve as antecedentbasis for use of such exclusive terminology as “solely,” “only” and thelike in connection with the recitation of claim elements, or use of a“negative” limitation.

Without the use of such exclusive terminology, the term “comprising” inthe claims shall allow for the inclusion of any additionalelement—irrespective of whether a given number of elements areenumerated in the claim, or the addition of a feature could be regardedas transforming the nature of an element set forth in the claims.

1. A surgical device for coagulating soft tissue of organs and for usewith a vacuum source to improve contact with the soft tissue and a trackto position the device, the device comprising: a shaft; an energytransfer element; an elongate housing being flexible to conform to asurface of the soft tissue, the housing being located at a distalportion of the shaft and having a main cavity containing the energytransfer element, the housing having at least one opening in a side wallto expose the main cavity and allow the energy transfer element tocontact the soft tissue, the housing further including a track lumenextending along the housing having an opening at a distal end of thehousing such that the track lumen allows for the housing to be advancedover the track, where the track lumen is fluidly isolated from the maincavity.
 2. The surgical device of claim 1, where the housing issufficiently flexible to conform to a shape of the track.
 3. Thesurgical device of claim 1, where the track lumen extends out of theproximal end of the housing.
 4. The surgical device of claim 1, furthercomprising a track tubing extending through a portion of the housing,where the track lumen is within the track tubing.
 5. The surgical deviceof claim 4, where the housing further comprises a perfusion lumenfluidly coupled to the main cavity to allow fluid delivery into the maincavity.
 6. The surgical device of claim 5, where the track tubingextends through the perfusion lumen, where the track lumen is fluidlyinsulated from the perfusion lumen.
 7. The surgical device of claim 4,where the housing further includes a plug having at least two channels,where a first channel fluidly couples the perfusion lumen with the maincavity, and a second channel extends from the perfusion lumen throughthe distal end of the housing and contains the track tubing.
 8. Thesurgical device of claim 4, further comprising a lip located about atleast a portion of the opening and connected to the housing, the liphaving a free portion being unconnected to the housing such that thefree portion of the lip conforms to tissue improving the ability of thelip to form a seal against the soft tissue upon application of thevacuum source to the main cavity.
 9. The surgical device of claim 1,where the housing comprises a fluid delivery lumen in fluidcommunication with the main cavity.
 10. The surgical device of claim 9,further comprising a handle at a proximal end of the shaft, where thehandle comprises a fluid delivery port in fluid communication with thefluid delivery lumen, a main lumen extending through the shaft to themain lumen, a vacuum port in fluid communication with the main lumen anda connector for electrically coupling the element to a power supply. 11.The surgical device of claim 9, where the fluid delivery lumen extendsthrough a portion of the housing on top of and parallel to the maincavity and directly opposite to the opening, to minimize a width of thehousing.
 12. The surgical device of claim 9, where the fluid deliverylumen is in fluid communication with the main cavity at a distal end ofthe housing such that application of the vacuum source and creation ofthe seal while delivering fluid causes circulation of fluid over theelement and back through the main cavity.
 13. The surgical device ofclaim 9, further comprising a main lumen extending through the shaft tothe main cavity, where the main lumen extends through a top portion ofthe housing and where the fluid delivery lumen extends through a portionof the main lumen where the opening is on a bottom of the housingopposite to the lumens. 14.-58. (canceled)
 59. A method of coagulating alength of soft tissue in a body, the method comprising: placing a trackinto the body; advancing an elongate housing into the body over thetrack, where the elongate housing includes a main cavity and at leastone conductive element within the main cavity, where the conductiveelement is exposed at an opening in the elongate housing to create thelength of soft tissue, and where the elongate housing further includes atrack lumen extending therethrough and fluidly isolated from the maincavity, where the track passes through the track lumen; applying avacuum source to the main cavity to pull soft tissue into contact withthe conductive element; and energizing the conductive element tocoagulate the length of soft tissue.
 60. The method of claim 59, whereenergizing the conductive element comprises applying RF energy to theconductive element.
 61. The method of claim 59, where energizing theconductive element comprises applying electrical energy to theconductive element to resistive heat the conductive element.
 62. Themethod of claim 59, where the elongate housing is attached to a shaft,where the shaft includes a perfusion lumen in fluid communication withthe main cavity, and further comprising delivering a perfusing fluid tothe soft tissue through the perfusion lumen.
 63. The method of claim 62,where delivering the perfusing fluid comprises delivering the perfusingfluid simultaneously with applying the vacuum.
 64. The method of claim59, where placing the track into the body comprises shaping a portion ofthe track to have a profile, where on advancement of the elongatehousing over the portion causes the elongate housing to conform to theprofile.
 65. The method of claim 64, where the track comprises deviceselected from the group consisting of a wire, a steerable catheter, asteerable guide-wire, a shaped tube, and a shaped mandrel.
 66. Themethod of claim 59, where a lip surrounds the opening in the elongatehousing, where on applying the vacuum causes the lip to form a seal onthe soft tissue causing soft tissue to be drawn into the opening.